Silk polypeptides and articles made therefrom

Abstract

The present invention relates to silk polypeptides and articles made therefrom.

Description

[0001] AMSilk GmbH

[0002] Our Ref.: 558-127 PCT

[0003] SILK POLYPEPTIDES AND ARTICLES MADE THEREFROM

[0004] The present invention relates to silk polypeptides and articles made therefrom.

[0005] BACKGROUND OF THE INVENTION

[0006] Silk polypeptides represent a unique family of structural molecules. The molecular structure of many silks consists of large regions or domains of hydrophilic amino acids, segregated by relatively short and more hydrophobic regions. Silk polypeptides exhibit superior mechanical properties. They are promising materials for drug delivery and tissue engineering due to their biocompatibility, biodegradability, self-assembly, and controllable structure and morphology. Additionally, silk materials exhibit high encapsulation efficiency and controllable drug release kinetics due to the adjustment of crystalline P-sheet formation. The formation of silk polypeptide biomaterials, such as fibers, films, mats, scaffolds, or capsules, is well known in the art. Moreover, silk polypeptides are well known in the cosmetic field, e.g. as basic compounds.

[0007] However, there is still a need for new silk polypeptides which are characterized by special mechanical properties. Specifically, there remains a need for silk polypeptides that exhibit improved or specifically tailored mechanical properties for demanding applications. Conventional, naturally occurring silk polypeptides provide a remarkable set of performance characteristics, but their properties are limited by their native amino acid composition and sequence architecture.

[0008] The present inventors provide such new silk polypeptides. They overcome these limitations. They differ from naturally occurring silk polypeptides in their mechanical stability and their resulting performance characteristics.

[0009] Such improved mechanical performance can be achieved through defined sequence variations, including the introduction of specific amino acid residues, which influence the structure, assembly behaviour and intermolecular interactions of the polypeptides. The resulting materials offer an extended property profile that cannot be achieved with natural silk compositions and therefore enable new uses and improved performance in a wide range of technical and biomedical applications. SUMMARY OF THE INVENTION

[0010] In a first aspect, the present invention relates to a silk polypeptide comprising an amino acid sequence according to formula:

[0011] [AmB]n, [BAm]n,

[0012] [BAmB]n, [AmBAm]n,

[0013] [AmBAo]n, [BAmBAo]n, [AmBAoB]n,

[0014] [AmBAmBAm]n, [BAmBAmB]n, [BAm]nB,

[0015] Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Amwherein

[0016] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0017] B stands for an amino acid sequence according to SEQ ID NO: 2 or SEQ ID NO: 32, m is an integer between and including 1 and 80, o is an integer between and including 1 and 80, n is an integer between and including 1 and 10, and

[0018] Y is a spacer element comprising / consi sting of a linker molecule containing cysteine or lysine, under the proviso that if m and o are present, they differ from each other.

[0019] In a second aspect, the present invention relates to a nucleic acid molecule encoding the silk polypeptide of the first aspect.

[0020] In a third aspect, the present invention relates to a method for producing a silk polypeptide comprising the step of:

[0021] (i) expressing the nucleic acid molecule of the second aspect in a cell or synthesizing the nucleic acid molecule of the second aspect in an in vitro transcription / translation system, thereby producing the silk polypeptide.

[0022] In a fourth aspect, the present invention relates to a silk polypeptide multimer comprising at least two silk polypeptides of the first aspect.

[0023] In a fifth aspect, the present invention relates to an article comprising the silk polypeptide of the first aspect or the silk polypeptide multimer of the fourth aspect.

[0024] In a sixth aspect, the present invention relates to a method for producing an article comprising the steps of:

[0025] (i) providing a solution comprising the silk polypeptide of the first aspect or the silk polypeptide multimer of the fourth aspect, and

[0026] (ii) forming an article out of / from the solution provided in (i). In a seventh aspect, the present invention relates to the use of the silk polypeptide of the first aspect, the silk polypeptide multimer of the fourth aspect, or the article of the fifth aspect in the textile industry, cosmetics industry, medical industry, agricultural industry, bioelectronics and for composite materials. The composite materials preferably include fibers, films, foams, gels and particulates.

[0027] This summary of the invention does not necessarily describe all features of the present invention. Other embodiments will become apparent from a review of the ensuing detailed description.

[0028] DETAILED DESCRIPTION OF THE INVENTION

[0029] Definitions

[0030] Before the present invention is described in detail below, it is to be understood that this invention is not limited to the particular methodology, protocols and reagents described herein as these may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the appended claims. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art.

[0031] Preferably, the terms used herein are defined as described in “A multilingual glossary of biotechnological terms: (TUPAC Recommendations)”, Leuenberger, H.G.W, Nagel, B. and Kolbl, H. eds. (1995), Helvetica Chimica Acta, CH-4010 Basel, Switzerland).

[0032] Several documents are cited throughout the text of this specification. Each of the documents cited herein (including all patents, patent applications, scientific publications, manufacturer's specifications, instructions, GenBank Accession Number sequence submissions etc.), whether supra or infra, is hereby incorporated by reference in its entirety. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.

[0033] In the following, the elements of the present invention will be described. These elements are listed with specific embodiments; however, it should be understood that they may be combined in any manner and in any number to create additional embodiments. The variously described examples and preferred embodiments should not be construed to limit the present invention to only the explicitly described embodiments. This description should be understood to support and encompass embodiments which combine the explicitly described embodiments with any number of the disclosed and / or preferred elements. Furthermore, any permutations and combinations of all described elements in this application should be considered disclosed by the description of the present application unless the context indicates otherwise.

[0034] The term “comprise” or variations such as “comprises” or “comprising” according to the present invention means the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. The term “consisting essentially of’ according to the present invention means the inclusion of a stated integer or group of integers, while excluding modifications or other integers which would materially affect or alter the stated integer. The term “consisting of’ or variations such as “consists of’ according to the present invention means the inclusion of a stated integer or group of integers and the exclusion of any other integer or group of integers.

[0035] The terms “a” and “an” and “the” and similar reference used in the context of describing the invention (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0036] The terms “polypeptide” and “protein” are used interchangeably in the context of the present invention. They refer to a long peptide-linked chain of amino acids, e.g. one that is at least 20 amino acids long.

[0037] The term “silk polypeptide”, as used herein, refers to a polypeptide which shows, in comparison to other polypeptides, a quite aberrant amino acid composition. In particular, a silk polypeptide possesses large quantities of alanine, glycine, proline, and serine. In addition, a silk polypeptide contains highly repetitive amino acid sequences or repetitive units (repeat units, modules), especially in their large core domain.

[0038] Based on DNA analysis, it was shown that all silk polypeptide are chains of repetitive units which further comprise a limited set of distinct shorter peptide motifs. The expressions “peptide motif’ and “consensus sequence” can be used interchangeably herein. Generally, the silk consensus sequences can be grouped into four major categories: GPGXX, GGX, Axor (GA)nand spacers. These categories of peptide motifs in silk proteins have been assigned structural roles. For example, it has been suggested that the GPGXX motif is involved in a P-turn spiral, probably providing elasticity. The GGX motif is known to be responsible for a glycine-rich 3i- helix. Both GPGXX and GGX motifs are thought to be involved in the formation of an amorphous matrix that connects crystalline regions, thereby providing elasticity of the fiber. Alanine-rich motifs typically contain 6-9 residues and have been found to form crystalline P- sheets. The spacers typically contain charged groups and separate the iterated peptide motifs into clusters. The silk polypeptide, as described herein, can perform “self-assembly”. The term “recombinant silk polypeptide”, as used herein, refers to a molecule which is biotechnologically or recombinantly produced in host organisms. The recombinant production of a silk polypeptide is, for example, described in Current Biology, Vol. 14, 2070-2074, 2004 and Current Biology, Vol. 14, 2070-2074, November 23, 2004. The recombinant silk polypeptide has been created using transformed host cells or transiently transfected cell cultures. In turn, the term “synthetic silk polypeptide”, as used herein, refers to a molecule that is produced chemically or biochemically.

[0039] Chemical silk polypeptide production allows the precise control of the synthesis of desired sequences. For example, a silk polypeptide can be synthesized chemically via a two-step chemical synthesis method, that is, chemoenzymatic polymerization, e.g. using papain, followed by postpolycondensation, e.g. using polyphosphoric acid as a condensing agent.

[0040] Biochemical silk polypeptide production may be carried out in an in vitro transcription / translation system. This system is cell-free. Cell-free protein synthesis means the in vitro production of proteins without living cells. Instead, special cell extracts or lysates are used, which contain the protein synthesis apparatus and all other necessary components. In principle, extracts for cell-free protein expression can be obtained from any type of cell. However, systems based on E. coli, wheat germ, rabbit reticulocytes and insect cells are most frequently used. After the addition of amino acids, an energy source, salts and other cofactors, theoretically any protein encoded by a DNA or RNA template can be synthesized. The in vitro synthesis of proteins in cell-free extracts is an important tool for molecular biologists and has a variety of applications, including the rapid identification of gene products (e.g. proteomics), localization of mutations through synthesis of truncated gene products, protein folding studies, and incorporation of modified or unnatural amino acids for functional studies.

[0041] The use of in vitro translation systems can have advantages over in vivo gene expression when the over-expressed product is toxic to the host cell, when the product is insoluble or forms inclusion bodies, or when the protein undergoes rapid proteolytic degradation by intracellular proteases.

[0042] Diverse in vitro protein synthesis kits are available on the market. The firm BioLabs, for example, offers a PURExpress® in vitro protein synthesis kit. The PURExpress® in vitro protein synthesis kit is a cell-free transcription / translation system and consists of defined, reconstituted and highly purified components of the E. coli transcription / translation apparatus. All protein factors are produced recombinantly as His-tag fusions, the ribosomes and tRNAs are highly purified from E. coli. This means that the system is free of contaminating exonucleases, RNases and proteases. The firm Promega provides, for example, a TNT® Quick coupled transcription / translation system which might also be an option. The LEXSY in vitro translation system (Jena Bioscience) applies T7 RNA polymerase to generate target mRNA and cell extracts with functional ribosomes and other essential components for cell-free protein synthesis.

[0043] The term “self-assembly”, as used herein, refers to a process in which a disordered system of pre-existing polypeptides forms an organized structure or pattern as a consequence of specific, local interactions (e.g. van der Waals forces, hydrophobic interactions, hydrogen bonds, disulfide bonds and / or salt-bridges, etc.) among the polypeptides themselves, without external direction or trigger although external factors might influence speed and nature of selfassembly. This particularly means that when two or more disordered and / or unfolded polypeptides are brought into contact, they interact with each other and consequently form a three-dimensional structure. This three-dimensional structure can also be considered as a polypeptide aggregate. The change from a disordered system to an organized structure or pattern during self-assembly is characterized by a transition from a fluid state to a fibrillary or gelatinous / gel-like and / or solid state and a corresponding increase in viscosity. The transition from a fluid state to a gelatinous / gel-like and / or solid state can be monitored, for example, by optical measurement or rheology. These techniques are known to the skilled person. The transition from a fluid state to a gelatinous / gel-like and / or solid state can be monitored, for example, using optical methods. As mentioned above, polypeptide aggregates are formed during the process of self-assembly.

[0044] The term “silk polypeptide fiber”, as used herein, refers to an object that is significantly longer than it is wide. It comprises or consists of the silk polypeptide of the present invention. The term “silk polypeptide fiber”, as used herein, also encompasses a monofilament or multifilament silk polypeptide fiber. A monofilament silk polypeptide fiber is composed of a single (mono)filament. A multifilament silk polypeptide fiber is composed of a number of (mono)filaments. For example, a multifilament fiber may be composed of between 2 and 1000 (mono)filaments, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000 (mono)filaments. The silk polypeptide fibers can be produced by wet or dry spinning, air-gap spinning, wet-extrusion spinning. Preferably, the silk polypeptide fibers of the present invention are produced by wet spinning. The term “silk polypeptide fiber”, as used herein, further encompasses single-drawn and multidrawn (e.g. double-drawn) silk polypeptide fibers. Said silk polypeptide fibers have been stretched one or more times during their preparation process.

[0045] The term “wet spinning”, as used herein, refers to the production process of silk polypeptide fibers from polymer solutions that are injected or extruded into a precipitation / coagulation bath comprising a solvent. The polymer precipitates and one or more filaments can be wound up as a fiber, specifically after several further processing steps, e.g. one or more drawing steps. The wet spinning process is used for polymers that either cannot be melted, are very temperature-sensitive, or can only be processed in special solvent systems. The silk polypeptide fibers can subsequently be drawn / stretched to increase strength and orientation. This may be done while the polymer is still solidifying or after it has been formed. The solvent used for the precipitation / coagulation bath may be a molecule containing at least one hydroxyl group, e.g. methanol, ethanol, butanol, propanol, isopropanol, Hexafluorisopropanol (HFIP), or polyethylene gycol (PEG).

[0046] The term “drawing”, as used herein, refers to a technique in which the cross-sectional area of the silk polypeptide fiber is reduced. It is preferred that drawing leads to a reduction of the cross-sectional area of the silk polypeptide fiber of at least 10%, at least 20%, at least 30%, at least 40%, of least 50%, at least 60%, at least 70%, or at least 80%. An extruded silk polypeptide fiber can be drawn. Alternatively, an already drawn silk polypeptide fiber can be drawn again (e.g. in a multi-stage drawing). The drawing of the silk polypeptide fibers leads to a silk polypeptide fiber extension. It is preferred that the extension is by at least 2-fold, at least 4-fold, at least 5-fold, at least 6-fold, at least 7-fold, or at least 8-fold in comparison to the length of the silk polypeptide as extruded or as already drawn. Preferably, such extension / drawing is carried out in the presence of the coagulation solution, washing solution, or during drying of the fiber, e.g. the silk polypeptide is at least partially submerged in the coagulation solution. This solution may also be designated as stretching solution. It can have the same composition as the coagulation solution. The coagulation solution may be a solution comprising a molecule containing at least one hydroxyl group, e.g. methanol, ethanol, butanol, isopropanol, Hexafluorisopropanol (HFIP), or polyethylene gycol (PEG).

[0047] Without wishing to be bound by any theory it is believed that the silk polypeptide fiber drawing leads to an alignment and more regular distribution of the silk polypeptide molecules within the fiber and, thereby, improves the mechanical properties of the fiber. Such extension can be carried out in a continuous or discontinuous process. In the continuous process it is preferred that the fiber is exposed to a pulling force. The term “silk polypeptide yarn”, as used herein, refers to an object composed of silk polypeptide fibers of the present invention. The silk polypeptide yarn can be spun from silk polypeptide fibers, e.g. wet using a chemi cal -technical wet spinning process or dry using a mechanical spinning process. The silk polypeptide yam can also be produced by twisting single silk polypeptide fibers. During twisting, individual silk polypeptide fibers are turned together in order to achieve a silk polypeptide yarn with improved tensile strength. The yam comprising the silk polypeptide of the present invention can be used in the textile industry, e.g. in order to produce fabrics, e.g. woven and non-woven fabrics. It has an excellent tensile strength and tearresistance.

[0048] The term “article”, as used herein, refers to any object which is produced from the silk polypeptide of the present invention. The article comprises or consists of the silk polypeptide of the present invention. The article is preferably a fiber, a yarn, more preferably a fabric comprising the yarn, or a film comprising the silk polypeptide of the present invention. The fabric may be a woven or non-woven fabric.

[0049] The term “solvent”, as used herein, refers to an aqueous solution or a solution comprising alcohol. It is preferred that the aqueous solution is a buffered aqueous solution, such as Tris / HCl, or water (H2O), such as technical H2O or deionized H2O. In another preferred embodiment the water may be piped water, rainwater, or seawater. It is also preferred that the alcohol is ethanol or isopropanol.

[0050] Embodiments of the invention

[0051] Silk polypeptides represent a unique family of structural molecules. The molecular structure of many silks consists of large regions or domains of hydrophilic amino acids, segregated by relatively short and more hydrophobic regions. Silk polypeptides exhibit superior mechanical properties. They are promising materials for drug delivery and tissue engineering due to their biocompatibility, biodegradability, self-assembly, and controllable structure and morphology. Additionally, silk materials exhibit high encapsulation efficiency and controllable drug release kinetics due to the adjustment of crystalline P-sheet formation. The formation of silk polypeptide biomaterials, such as fibers, films, mats, scaffolds, or capsules, is well known in the art. Moreover, silk polypeptides are well known in the cosmetic field, e.g. as basic compounds.

[0052] However, there is still a need for new silk polypeptides which are characterized by special mechanical properties. The present inventors provide such new silk polypeptides. They differ from naturally occurring silk polypeptides in their mechanical stability. Thus, in a first aspect, the present invention relates to a (synthetic / recombinant) silk polypeptide comprising an amino acid sequence according to formula: [AmB]n, [BAm]n, [BAmB]n, [AmBAm]n, [AmBAo]n, [BAmBAo]n, [AmBAoB]n, [AmBAmBAm]n, [BAmBAmB]n, [BAm]nB, Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Amwherein

[0053] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0054] B stands for an amino acid sequence according to SEQ ID NO: 2 or SEQ ID NO: 32, m is an integer between and including 1 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0055] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0056] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, o is an integer between and including 1 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0057] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0058] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0059] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, n is an integer between and including 1 and 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and

[0060] Y is a spacer element comprising / consi sting of a linker molecule containing cysteine or lysine, under the proviso that if m and o are present, they / the integers differ from each other.

[0061] The silk polypeptide is specifically a (synthetic / recombinant) spider silk polypeptide.

[0062] The amino acid sequence according to SEQ ID NO: 1 is based on / derived from the amino acid sequence of ADF-4 of the spider Araneus diadematus. Specifically, the amino acid sequence according to SEQ ID NO: 1 is

[0063] GSSAAAAAAAASGPGGYGPENQGPSGPGGYGPGGP. The amino acid sequence according to SEQ ID NO: 2 is GSSAAAAAAAASGPGGYGPENQGPCGPGGYGPGGP. The amino acid sequence according to SEQ ID NO: 32 is

[0064] GSSAAAAAAAASGPGGYGPKNQGPSGPGGYGPGGP. The amino acid sequence according to SEQ ID NO: 2, namely

[0065] GSSAAAAAAAASGPGGYGPENQGPCGPGGYGPGGP, differs from the amino acid sequence according to SEQ ID NO: 1, namely

[0066] GSSAAAAAAAASGPGGYGPENQGPSGPGGYGPGGP, in that the amino acid S (Ser / Serine) at position 25 has been replaced by the amino acid C (Cys / Cysteine). In addition, the amino acid sequence according to SEQ ID NO: 32, namely GSSAAAAAAAASGPGGYGPKNQGPSGPGGYGPGGP, differs from the amino acid sequence according to SEQ ID NO: 1, namely

[0067] GSSAAAAAAAASGPGGYGPENQGPSGPGGYGPGGP, in that the amino acid E (Glu / glutamic acid) at position 20 has been replaced by the amino acid K (Lys / Lysine).

[0068] Accordingly, in one embodiment, the present invention relates to a (synthetic / recombinant) silk polypeptide comprising an amino acid sequence according to formula:

[0069] [AmB]n, [BAm]n,

[0070] [BAmB]n, [AmBAm]n,

[0071] [AmBAo]n, [BAmBAo]n, [AmBAoB]n,

[0072] [AmBAmBAm]n, [BAmBAmB]n, [BAm]nB,

[0073] Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Amwherein

[0074] A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2, m is an integer between and including 1 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0075] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0076] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, o is an integer between and including 1 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0077] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0078] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0079] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, n is an integer between and including 1 and 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and

[0080] Y is a spacer element comprising / consi sting of a linker molecule containing cysteine, under the proviso that if m and o are present, they / the integers differ from each other.

[0081] In one another embodiment, the present invention relates to a (synthetic / recombinant) silk polypeptide comprising an amino acid sequence according to formula: [AmB]n, [BAm]n, [BAmB]n, [AmBAm]n,

[0082] [AmBAo]n, [BAmBAo]n, [AmBAoB]n,

[0083] [AmBAmBAm]n, [BAmBAmB]n, [BAm]nB, Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Am wherein

[0084] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0085] B stands for an amino acid sequence according to SEQ ID NO: 32, m is an integer between and including 1 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0086] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0087] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, o is an integer between and including 1 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0088] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0089] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0090] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, n is an integer between and including 1 and 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and

[0091] Y is a spacer element comprising / consi sting of a linker molecule containing lysine, under the proviso that if m and o are present, they / the integers differ from each other.

[0092] Preferably, the silk polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 3, SEQ ID NO: 4, and SEQ ID NO: 5.

[0093] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [AmB]i, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0094] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0095] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0096] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0097] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]2, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0098] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0099] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0100] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0101] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]s, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0102] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0103] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0104] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0105] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]4, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0106] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0107] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0108] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0109] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]s, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0110] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0111] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0112] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0113] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]e, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0114] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0115] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0116] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0117] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]?, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0118] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0119] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0120] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0121] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]s, wherein A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0122] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0123] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0124] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmB]9, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0125] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0126] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0127] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0128] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [AmB]io, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0129] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0130] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0131] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0132] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80.

[0133] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [AmB]i, wherein

[0134] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0135] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48. Even more preferably, the silk polypeptide comprises an amino acid sequence according to SEQ ID NO: 22.

[0136] Alternatively, the silk polypeptide comprises an amino acid sequence according to formula [AmB]2, wherein

[0137] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0138] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48.

[0139] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [BAm]i, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0140] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0141] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0142] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0143] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]2, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0144] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0145] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0146] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0147] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]3, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0148] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0149] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0150] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0151] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]4, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0152] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0153] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0154] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0155] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]s, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0156] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0157] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0158] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0159] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]e, wherein A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0160] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0161] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0162] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]?, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0163] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0164] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0165] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0166] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]8, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0167] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0168] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0169] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0170] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]9, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0171] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0172] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0173] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0174] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [BAm]io, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0175] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0176] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0177] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0178] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80. More preferably, the silk polypeptide comprises an amino acid sequence according to formula [BAm]i, wherein

[0179] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0180] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48.

[0181] Alternative, the silk polypeptide comprises an amino acid sequence according to formula [BAm]2, wherein

[0182] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0183] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48.

[0184] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]i, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0185] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0186] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0187] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0188] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]2, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0189] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0190] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0191] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0192] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]3, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0193] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0194] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0195] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0196] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]4, wherein A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0197] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0198] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0199] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]s, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0200] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0201] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0202] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0203] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]e, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0204] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0205] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0206] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0207] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]7, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0208] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0209] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0210] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0211] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]s, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0212] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0213] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0214] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0215] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]9, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0216] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0217] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0218] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0219] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [BAmB]io, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0220] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0221] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0222] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0223] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80.

[0224] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [BAmB]i, wherein

[0225] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0226] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48. Even more preferably, the silk polypeptide comprises an amino acid sequence according to SEQ ID NO: 23 or an amino acid sequence according to SEQ ID NO: 41.

[0227] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]i, wherein

[0228] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0229] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0230] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0231] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0232] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]2, wherein

[0233] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0234] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]3, wherein

[0235] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0236] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0237] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0238] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0239] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]4, wherein

[0240] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0241] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0242] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0243] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0244] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]5, wherein

[0245] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0246] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0247] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0248] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0249] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]6, wherein

[0250] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0251] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0252] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0253] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0254] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]7, wherein

[0255] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0256] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0257] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0258] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0259] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]8, wherein

[0260] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0261] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0262] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0263] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0264] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]9, wherein

[0265] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0266] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0267] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0268] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0269] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [AmBAm]io, wherein

[0270] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0271] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0272] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0273] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0274] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80.

[0275] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [AmBAm]i, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0276] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48.

[0277] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]i, wherein

[0278] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0279] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0280] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0281] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0282] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]2, wherein

[0283] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0284] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0285] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0286] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0287] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]3, wherein

[0288] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0289] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0290] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0291] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0292] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]4, wherein

[0293] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0294] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]5, wherein

[0295] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0296] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0297] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0298] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0299] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]6, wherein

[0300] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0301] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0302] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0303] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0304] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]7, wherein

[0305] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0306] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0307] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0308] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0309] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]8, wherein

[0310] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0311] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0312] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0313] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0314] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]9, wherein

[0315] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0316] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0317] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0318] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0319] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [AmBAmBAm]io, wherein

[0320] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0321] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0322] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0323] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0324] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80.

[0325] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [AmBAmBAm]i, wherein

[0326] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0327] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48. Even more preferably, the silk polypeptide comprises an amino acid sequence according to SEQ ID NO: 24.

[0328] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]i, wherein

[0329] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0330] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0331] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0332] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0333] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]2, wherein

[0334] A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0335] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0336] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0337] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]3, wherein

[0338] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0339] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0340] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0341] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0342] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]4, wherein

[0343] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0344] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0345] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0346] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0347] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]5, wherein

[0348] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0349] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0350] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0351] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0352] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]6, wherein

[0353] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0354] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0355] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0356] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0357] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]7, wherein

[0358] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0359] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0360] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0361] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0362] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]8, wherein

[0363] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0364] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0365] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0366] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0367] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]9, wherein

[0368] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0369] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0370] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0371] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0372] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [BAmBAmB]io, wherein

[0373] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0374] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80.

[0375] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [BAmBAmB]i, wherein

[0376] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0377] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48.

[0378] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]i, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0379] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0380] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0381] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0382] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0383] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0384] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]2, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0385] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0386] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0387] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0388] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0389] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0390] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]3, wherein A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0391] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0392] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0393] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0394] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0395] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]4, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0396] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0397] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0398] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0399] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0400] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0401] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]5, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0402] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0403] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0404] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0405] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0406] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0407] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]6, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0408] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0409] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0410] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0411] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0412] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0413] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]7, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0414] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0415] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0416] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0417] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0418] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0419] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]8, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0420] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0421] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0422] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0423] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0424] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]9, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0425] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0426] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0427] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0428] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0429] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0430] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, or a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0]io, wherein

[0431] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0432] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0433] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0434] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0435] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0436] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0437] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other,

[0438] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [AmBA0]i, wherein

[0439] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0440] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 8 and o is 16, o is 8 and m is 16, m is 8 and o is 32, o is 8 and m is 32, m is 8 and o is 48, o is 8 and m is 48, m is 16 and o is 32, o is 16 and m is 32, m is 16 and o is 48, o is 16 and m is 48, m is 32 and o is 16, o is 32 and m is 16, m is 32 and o is 48, or o is 48 and m is 32.

[0441] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]i, wherein

[0442] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0443] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0444] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0445] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0446] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0447] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0448] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]2, wherein

[0449] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0450] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0451] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0452] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0453] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0454] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0455] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]3, wherein

[0456] A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0457] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0458] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0459] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0460] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0461] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]4, wherein

[0462] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0463] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0464] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0465] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0466] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0467] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0468] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]5, wherein

[0469] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0470] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0471] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0472] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0473] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0474] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]6, wherein

[0475] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0476] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0477] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0478] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0479] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0480] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0481] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]7, wherein

[0482] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0483] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0484] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0485] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0486] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0487] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0488] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]8, wherein

[0489] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0490] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]9, wherein

[0491] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0492] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0493] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0494] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0495] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0496] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0497] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, or a silk polypeptide comprising an amino acid sequence according to formula: [BAmBA0]io, wherein

[0498] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0499] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0500] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0501] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0502] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0503] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0504] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, More preferably, the silk polypeptide comprises an amino acid sequence according to formula [BAmBA0]i, wherein

[0505] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0506] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 8 and o is 16, o is 8 and m is 16, m is 8 and o is 32, o is 8 and m is 32, m is 8 and o is 48, o is 8 and m is 48, m is 16 and o is 32, o is 16 and m is 32, m is 16 and o is 48, o is 16 and m is 48, m is 32 and o is 16, o is 32 and m is 16, m is 32 and o is 48, or o is 48 and m is 32.

[0507] Even more preferably, the spider silk polypeptide comprises an amino acid sequence according to SEQ ID NO: 25.

[0508] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]i, wherein

[0509] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0510] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0511] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0512] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0513] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0514] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0515] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]2, wherein

[0516] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0517] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]3, wherein

[0518] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0519] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0520] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0521] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0522] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0523] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0524] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]4, wherein

[0525] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0526] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0527] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0528] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0529] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0530] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0531] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]5, wherein

[0532] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0533] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0534] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0535] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0536] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0537] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0538] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]6, wherein

[0539] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0540] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0541] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0542] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0543] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0544] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0545] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]7, wherein

[0546] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0547] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0548] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0549] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0550] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]8, wherein

[0551] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0552] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0553] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0554] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0555] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0556] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0557] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]9, wherein

[0558] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0559] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0560] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0561] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0562] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0563] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0564] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other, or a silk polypeptide comprising an amino acid sequence according to formula: [AmBA0B]io, wherein

[0565] A stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0566] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0567] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, and o is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0568] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0569] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0570] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, under the proviso that m and o differ from each other,

[0571] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [AmBA0B]i, wherein

[0572] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0573] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 8 and o is 16, o is 8 and m is 16, m is 8 and o is 32, o is 8 and m is 32, m is 8 and o is 48, o is 8 and m is 48, m is 16 and o is 32, o is 16 and m is 32, m is 16 and o is 48, o is 16 and m is 48, m is 32 and o is 16, o is 32 and m is 16, m is 32 and o is 48, or o is 48 and m is 32.

[0574] Accordingly, the following silk polypeptides are exemplary encompassed: a silk polypeptide comprising an amino acid sequence according to formula: [BAm]iB, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0575] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0576] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0577] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0578] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]2B, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0579] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0580] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]3B, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0581] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0582] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0583] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0584] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]4B, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0585] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0586] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0587] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0588] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]sB, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0589] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0590] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0591] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0592] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]eB, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0593] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0594] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0595] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0596] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]?B, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0597] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0598] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0599] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0600] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]8B, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0601] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0602] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0603] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0604] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, a silk polypeptide comprising an amino acid sequence according to formula: [BAm]9B, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0605] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0606] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0607] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0608] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, or a silk polypeptide comprising an amino acid sequence according to formula: [BAm]ioB, wherein A stands for an amino acid sequence according to SEQ ID NO: 1,

[0609] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0610] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0611] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0612] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80.

[0613] More preferably, the silk polypeptide comprises an amino acid sequence according to formula [BAm]3B, wherein

[0614] A stands for an amino acid sequence according to SEQ ID NO: 1,

[0615] B stands for an amino acid sequence according to SEQ ID NO: 2 (or SEQ ID NO: 32), and m is 16, 32, or 48.

[0616] Even more preferably, the silk polypeptide comprises an amino acid sequence according to SEQ ID NO: 33.

[0617] It should be noted that in all the above embodiments, the amino acid sequence according to SEQ ID NO: 2 can be replaced by the amino acid sequence according to SEQ ID NO: 32. The silk polypeptide may be attached / linked / fused to a N-terminal tag. This tag allows the purification of the silk polypeptide after its production. This N-terminal tag may have an amino acid sequence according to SEQ ID NO: 30 (MASMTGGQQMG). The silk polypeptide may further contain N-terminally a sequence derived from silk polypeptide cloning having an amino acid sequence according to SEQ ID NO: 31 (RGSM) and / or C-terminally a single G derived from silk polypeptide cloning. The N- and C-terminally attachments may specifically be of importance in cases where the silk polypeptide consists of the above amino acid sequences. Silk polypeptides comprising the N-terminal tag and the sequence derived from silk polypeptide cloning have exemplary an amino acid sequence according to SEQ ID NO: 26, SEQ ID NO: 27, SEQ ID NO: 28, SEQ ID NO: 29, SEQ ID NO: 34, or SEQ ID NO: 42.

[0618] Alternatively, the silk polypeptide comprises an amino acid sequence according to formula: Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Amwherein

[0619] A stands for an amino acid sequence according to SEQ ID NO: 1, m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0620] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0621] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0622] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, n is an integer between and including 1 and 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and

[0623] Y is a spacer element comprising / consi sting of a linker molecule containing cysteine or lysine.

[0624] Thus, in one embodiment, the silk polypeptide comprises an amino acid sequence according to formula: Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Amwherein A stands for an amino acid sequence according to SEQ ID NO: 1, m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,

[0625] 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,

[0626] 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,

[0627] 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, n is an integer between and including 1 and 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and

[0628] Y is a spacer element comprising / consi sting of a linker molecule containing cysteine.

[0629] In one another embodiment, the silk polypeptide comprises an amino acid sequence according to formula: Am-Y, Y-Am, Y-Am-Y, or Am-Yn-Amwherein A stands for an amino acid sequence according to SEQ ID NO: 1, m is an integer between and including 2 and 80, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80, n is an integer between and including 1 and 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and

[0630] Y is a spacer element comprising / consi sting of a linker molecule containing lysine.

[0631] Preferably, the linker molecule containing cysteine is selected from the group consisting of an amino acid sequence according to SEQ ID NO: 6 (GGCGGSGG GGSGGGG), SEQ ID NO: 7 (GGCGGSGG), SEQ ID NO: 8 (GGCGGSG), and SEQ ID NO: 9 (GSGCGGSG GGGSGGG) or the linker molecule containing lysine is SEQ ID NO: 35 (PKN).

[0632] More preferably, the spacer element comprising the linker molecule containing cysteine is selected from the group consisting of an amino acid sequence according to SEQ ID NO: 10 (RGGCGGSGG GGSGGGGGSM), SEQ ID NO: 11 (RGGCGGSGG GSM), SEQ ID NO: 12 (RGSGGCGGS G), and SEQ ID NO: 13 (RGSGCGGSG GGGSGGG) or the spacer element comprising / consi sting of the linker molecule containing lysine is SEQ ID NO: 36 (PKNRGSM).

[0633] Even more preferably, the silk polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO:

[0634] 17, and SEQ ID NO: 37.

[0635] The silk polypeptide may be attached / linked / fused to a N-terminal tag. This N-terminal tag may have an amino acid sequence according to SEQ ID NO: 30 (MASMTGGQQMG). C- terminally, a single G derived from silk polypeptide cloning may (additionally or alternatively) be present. The N- and C-terminally attachments may specifically be of importance in cases where the silk polypeptide consists of the above amino acid sequences. Silk polypeptides comprising a N-terminal tag have exemplary an amino acid sequence according to SEQ ID NO:

[0636] 18, SEQ ID NO: 19, SEQ ID NO: 20, SEQ ID NO: 21, or SEQ ID NO: 38.

[0637] The present inventors found that the introduction of a cysteine (C) residue in the above amino acid sequences confers several potential advantages for fiber formation:

[0638] 1. Disulfide Bond Formation:

[0639] • Cysteine's thiol group (-SH) allows it to form disulfide bonds (S-S) with other cysteine residues. This helps cross-linking of silk polypeptides, leading to: o Enhanced strength: Disulfide bonds can reinforce the structural integrity of the silk fibers, making them more resilient. o Increased stability: Cross-links can stabilize the fiber network, increasing resistance to deformation under mechanical stress. o Control of elasticity: Disulfide bonds might allow controlled elasticity, adding to the silk's flexibility when needed and stiffening it in response to strain. o Increase of viscosity e.g. in spin dope solution

[0640] 2. Controlled Polymerization:

[0641] • Cysteines mediate controlled polymerization of the silk polypeptides during fiber spinning, ensuring that fiber formation is properly regulated. This enhances the orderly assembly of silk polypeptides into highly organized P-sheet structures, which contribute to the strength and toughness of the silk polypeptides.

[0642] 3. Redox Regulation:

[0643] • Cysteine residues are sensitive to oxidative environments, meaning their disulfide bonds can be broken and reformed in response to redox changes. This redox regulation provides a self-healing mechanism for silk fibers, allowing disulfide bonds to break and reform under certain conditions, repairing damage and extending the functional life of the fiber.

[0644] 4. Protein Folding Assistance:

[0645] • Cysteines can assist in proper protein folding by forming transient or permanent disulfide bonds, which help the protein adopt its correct conformation more efficiently. This is particularly useful in the spinning process of silk, where rapid folding and assembly are critical for producing strong and orderly fibers.

[0646] • Cysteines can further assist in hierarchical assembly of proteins / protein folding. Disulfide bonds may help deliver optimal stacking for maximum tenacity but also maximum proximity of the cysteine in aggregated form to trigger efficient multimerization

[0647] 5. Biomaterial Engineering:

[0648] • In the context of genetic engineering or biomaterial applications, the inclusion of cysteine provides a means to chemically modify the silk. Cysteines are reactive and can be targeted for modifications such as conjugation with other molecules (e.g., for functionalization or cross-linking in engineered materials).

[0649] Thus, cysteine residues in silk polypeptide sequences enhance fiber strength, elasticity, stability, and even offer self-healing properties through the formation of disulfide bonds. Cysteine residues in silk polypeptide sequences also play a role in controlling polymerization during the silk spinning process, contributing to the unique mechanical properties that make silk polypeptides so versatile and robust. Lysine residues in silk polypeptide sequences offer a versatile tool for material development and functionalization. In contrast to cysteine, which contributes to structural cross-linking through disulfide bonds, the primary amino groups of lysine provide highly reactive sites for chemical modification, conjugation, or enzymatic cross-linking. The positive charge of lysine enhances electrostatic interactions, stability of protein solutions, and can therefore improve processability during fiber spinning. In addition, lysines serve as anchoring points for the attachment of functional components, supporting the development of intelligent, responsive, or bioactive fiber materials. While lysine plays a smaller role in disulfide-mediated networking, it opens up a broad range of chemical flexibility and functional expansion in biomaterial applications. For example, the present inventors could show that with glutaraldehyde / glyoxal as crosslinker in the spin dope or in an aqueous solution before spin dope preparation, a higher dope viscosity and molecular weight (MW) have been achieved. In addition, the present inventors could show that with glutaraldehyde as crosslinker after spinning, a molecular weight (MW) increase has been achieved.

[0650] In a second aspect, the present invention relates to a nucleic acid molecule encoding the silk polypeptide of the first aspect.

[0651] The nucleic acid molecule may be incorporated in a vector. Preferably, the vector, e.g. plasmid or viral vector, is an expression vector.

[0652] In a third aspect, the present invention relates to a method for producing a silk polypeptide comprising the step of:

[0653] (i) expressing the nucleic acid molecule of the second aspect in a cell or synthesizing the nucleic acid molecule of the second aspect in an in vitro transcription / translation system, thereby producing the silk polypeptide.

[0654] In one embodiment, the silk polypeptide is produced recombinantly within a cell. The cell may also be named host cell. The cell may be a prokaryotic or eukaryotic cell. The prokaryotic cell may be an E. coli cell, a Bacillus cell, a Bacillus licheniformis,a Bacillus amyloliquefaciens cell, a Bacillus megaterium cell, a Bacillus brevis cell, a Corynebacterium cell, a Streptomyces S. lividans cell, a Lactococcus lactis cell, a Staphylococcus cell, a S. carnosus cell or a Pseudomonas aeroginosa cell. The eukaryotic cell may be a mammalian cell, a plant cell, a yeast cell, a fungi cell, or an insect cell. The mammalian cell may be a CHO, COS, HeLa, HEK293(T), or BHK cell. The yeast cell may be a Saccharomyces cerevisiae cell, a Schizosaccharomyces pombe cell, a Pichia pastoris cell, a Candida albicans cell, or a Hansenula polymorpha cell. The fungi cell may be an Aspergillus or a Trichoderma cell. The insect cell may be a Lepidoptera insect cell. The plant cell may be a tobacco cell, a potato cell, a com cell, a pea cell, or a tomato cell. The above-mentioned cells are preferably recombinant cells.

[0655] The nucleic acid molecule may be found inside the cell (i) freely dispersed as such, (ii) incorporated in a vector, or (iii) integrated into the cell genome or mitochondrial DNA. Preferably, the vector, e.g. plasmid or viral vector, is an expression vector.

[0656] The cell may be transformed, transfected, or infected with the nucleic acid molecule or the vector comprising the nucleic acid molecule.

[0657] In one another embodiment, the silk polypeptide is produced in an in vitro transcription / translation system. This system is cell-free. Cell-free protein synthesis means the in vitro production of proteins without living cells. Instead, special cell extracts or lysates are used, which contain the protein synthesis apparatus and all other necessary components. In principle, extracts for cell-free protein expression can be obtained from any type of cell. However, systems based on E. coli, wheat germ, rabbit reticulocytes and insect cells are most frequently used. After the addition of amino acids, an energy source, salts and other cofactors, theoretically any protein encoded by a DNA or RNA template can be synthesized.

[0658] Diverse in vitro protein synthesis kits are available on the market. The firm BioLabs, for example, offers a PURExpress® in vitro protein synthesis kit. The PURExpress® in vitro protein synthesis kit is a cell-free transcription / translation system and consists of defined, reconstituted and highly purified components of the E. coli transcription / translation apparatus. All protein factors are produced recombinantly as His-tag fusions, the ribosomes and tRNAs are highly purified from E. coli. This means that the system is free of contaminating exonucleases, RNases and proteases. The firm Promega provides, for example, a TNT® Quick coupled transcription / translation system which might be an option. The LEXSY in vitro translation system (Jena Bioscience) applies T7 RNA polymerase to generate target mRNA and cell extracts with functional ribosomes and other essential components for cell-free protein synthesis.

[0659] In one preferred embodiment, the method further comprises the step of:

[0660] (ii) isolating the silk polypeptide from the cell or in vitro transcription / translation system.

[0661] The isolation of the polypeptide from the cell or in vitro transcription / translation system may be achieved by separating said polypeptide from said cell or transcription / translation system via centrifugation, sedimentation, and / or filtration, e.g. via centrifugation and filtration, via sedimentation and filtration, via sedimentation and centrifugation, or via centrifugation, sedimentation, and filtration. Depending on the silk polypeptide to be harvested, the parameters for centrifugation, sedimentation, or filtration may vary. The person skilled in the art is able to easily adapt the appropriate separation parameters, e.g. the acceleration-force / g-force and / or time using centrifugation for separation, filter size using filtration for separation, and / or sedimentation time using sedimentation for separation, in order to harvest said polypeptide produced by said cells or said transcription / translation system.

[0662] After step (ii), further purification of the isolated silk polypeptide may be required. Said purification may be achieved via chromatography, preferably column chromatography, more preferably size exclusion chromatography, hydrophobic interaction chromatography, ion exchange chromatography, affinity chromatography, or high pressure liquid chromatography, electrophoresis, preferably gel electrophoresis, or ultracentrifugation.

[0663] In a fourth aspect, the present invention relates to a silk polypeptide multimer comprising at least two silk polypeptides of the first aspect.

[0664] Preferably, the silk polypeptide multimer is a dimer, trimer, or tetramer.

[0665] More preferably, the at least two silk polypeptides are connected to each other within the multimer via a covalent bound, specifically via the cysteine residues comprised in the silk polypeptides.

[0666] Such silk polypeptide multimers may be formed by the self-aggregation of the silk polypeptides in a host cell without the influence of the cellular scaffold or other intracellular mechanisms. Particularly, the silk polypeptide multimers may be formed by the selfaggregation of multiple copies / units of silk polypeptides into a body or solid mass without the influence of the cellular scaffold or other intracellular mechanisms. The silk polypeptide multimers may also be formed by self-aggregation of silk polypeptides in a suspension, e.g. in a cell culture medium, in an aqueous solution (e.g. buffered aqueous solution), in technical water, or in deionized water. The silk polypeptide multimers may be formed by several mechanisms which may include covalent or non-covalent interactions between the silk polypeptides. The silk polypeptide multimers may also be designated as aggregates.

[0667] In a fifth aspect, the present invention relates to an article comprising the silk polypeptide of the first aspect or the silk polypeptide multimer of the fourth aspect.

[0668] Preferably, the article is a fiber, more preferably a fabric comprising the fiber, a yarn, more preferably a fabric comprising the yarn, or a film. The fabric may be a woven or nonwoven fabric.

[0669] In a sixth aspect, the present invention relates to a method for producing an article comprising the steps of:

[0670] (i) providing a solution comprising the silk polypeptide of the first aspect or the silk polypeptide multimer of the fourth aspect, and (ii) forming an article out of / from the solution provided in (i).

[0671] In one preferred embodiment, the article is a fiber. The fiber is preferably formed by extruding the solution comprising the silk polypeptide of the first aspect.

[0672] Extrusion in this context means the application of pressure to the solution to force it through an opening, e.g. a nozzle. In the art of polymer technology, extrusion processes are often used to form fibers from molten therm oplasts, i.e. the entire extruded material solidifies after it has left the opening. In the context of the present invention, the extruded solution does not solidify entirely. Rather the dissolved polymers that are comprised in the extruded solution associate to form a fiber, which is typically smaller in diameter than the opening through which the solution is extruded, while the remaining solvent is separated from the fiber thus formed. In some embodiments, the fiber initially formed is attached to a fiber recovery device, e.g. a cylinder, spool or bobbin, onto which the fiber is continuously wound. Depending on the relative speed of the, e.g. cylinder, with respect to the speed of fiber formation during extrusion, there may also be a pulling force exerted onto the extruded fiber, i.e. the fiber in some embodiments may be considered to be drawn from the extruded solution.

[0673] The solution comprising the silk polypeptide may comprise formic acid, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), hexafluoroisopropanol (HFI) or ionic liquids as a solvent. The solution for extruding the silk polypeptide fiber may also be designated as dope solution.

[0674] Preferably, the extrusion of the silk polypeptide fiber is carried out into a coagulation bath. The extrusion can take place directly into the coagulation bath or via an air gap into the coagulation bath. The coagulation solution may be selected from the group consisting of water (H2O), methanol, ethanol, (EtOH), butanol, isopropanol, ethylene glycol, l-Ethyl-3- methylimidazoliumchlorid (EMIMC1), and N-Methylmorpholin-N-oxid (NMMO). In one more preferred embodiment, the fiber is (after its formation) extended in a subsequent stretching step. The extension may be at least 4-fold, at least 5-fold, at least 6-fold, at least 7-fold, at least 8- fold, or at least 10-fold. During the stretching step, the cross-sectional area of the fiber is reduced. It is preferred that stretching step leads to a reduction of the cross-sectional area of the silk polypeptide fiber of at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, or at least 70%.

[0675] For example, the thickness (diameter) of the fiber upon extrusion may be in the range of 5 pm to 200 pm and / or the thickness (diameter) of the fiber after extension may be in the range of 2.5 pm to 100 pm. Preferably, such stretching step is carried out in the presence of a coagulation solution, e.g. the silk polypeptide fiber is at least partially submerged in the coagulation solution. This solution is also referred to as stretching solution in the context of the present invention. It may have the same composition as the coagulation solution. The stretching solution may be selected from the group consisting of an aqueous solution, water (H2O), water vapor, methanol, and ethanol (EtOH).

[0676] In one even more preferred embodiment, the silk polypeptide fiber is subsequently spun into a yarn. The silk polypeptide yam can be spun from silk polypeptide fibers, e.g. wet using a chemi cal -technical wet spinning process or dry using a mechanical spinning process. Alternatively, the silk polypeptide yam is produced by twisting single silk polypeptide fibers. During twisting, individual silk polypeptide fibers are turned together in order to achieve a silk polypeptide yarn with improved tensile strength. The yarn comprising the silk polypeptide of the present invention can be used in the textile industry, e.g. in order to produce fabrics, e.g. woven and non-woven fabrics.

[0677] In another preferred embodiment, the article is a film. The film is preferably formed by applying the solution comprising the silk polypeptide of the first aspect. The solution comprising the silk polypeptide may be applied onto a (solid) support or (solid) substrate. Afterwards, the solution comprising the silk polypeptide of the first aspect is usually dried. The solution comprising the silk polypeptide of the first aspect may be applied by casting, spraying, or dropping said solution onto the support material or substrate. The film may finally be removed from the support material.

[0678] The produced silk polypeptide film is specifically a self-supporting film, i.e. a silk polypeptide film that has the capacity for supporting itself without the help of additional materials such as carrier elements.

[0679] The solution comprising the silk polypeptide may comprise formic acid, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), or hexafluoroisopropanol (HFIP) as a solvent. The solution for casting a silk polypeptide film may also be designated as casting solution.

[0680] The fiber of the fifth or sixth aspect preferably comprises / is blended with one or more additional polymers. For example, the silk polypeptide fiber may comprise / may be blended with one or more additional polymers selected from the group consisting of a collagen (e.g. natural and / or recombinant collagen), keratin, and polyolefins (e.g. polylactic acid (PLA), polycaprolactone (PCL), polylactat (PLA), polyhydroxybutyrate (PHB)) and polyacrylate. More particularly, the content of the one or more additional polymers in the silk polypeptide fiber is less than 50% by weight, less than 40% by weight, less than 30% by weight, less than 20% by weight, than 15% by weight, less than 10% by weight, less than 5% by weight, or less than 1% by weight and / or the content of the one or more additional polymers in the silk polypeptide fiber is at least 0.1% by weight, at least 1% by weight, at least 5% by weight, at least 10% by weight, at least 15% by weight, at least 20% by weight, at least 30% by weight, or at least 40% by weight. Such a silk polypeptide fiber may enhance any desired characteristics, e.g. appearance, softness, weight, durability, water-repellent properties, improved cost-of-manufacture, Said characteristics may be useful in medical, industrial, or commercial applications. The one or more additional polymers may be added to the dope / spinning solution. It is also possible that the one or more additional polymer fibers are twisted around / combined with one or more silk polypeptide fibers in a yam production process.

[0681] In a seventh aspect, the present invention relates to the use of the silk polypeptide of the first aspect, the silk polypeptide multimer of the fourth aspect, or the article of the fifth aspect in the textile industry, cosmetics industry, medical industry, agricultural industry, bioelectronics and for composite materials. The composite materials preferably include fibers, films, foams, gels and particulates.

[0682] Alternatively, the silk polypeptide of the first aspect, the silk polypeptide multimer of the fourth aspect, or the article of the fifth aspect is used in high-performance textiles, biomedical applications, soft robotics and self-healing materials, advanced composites and coatings.

[0683] Specifically, the (synthetic or recombinant) silk polypeptide or fiber comprising the (synthetic or recombinant) silk polypeptide that incorporates cysteine or lysine residues can offer clear advantages in several fields. In high-performance textiles, such modified fibers could provide superior strength, controlled elasticity, and long-term durability, making them suitable for technical fabrics, ropes, sails, or protective gear. In biomedical applications, the presence of reactive cysteine or lysine groups allows precise functionalization with drugs, enzymes, growth factors, or cell-adhesive peptides, which is highly valuable for sutures, wound dressings, scaffolds, and implant coatings that require biocompatibility and controlled degradation. In soft robotics and self-healing materials, disulfide bond dynamics from cysteine residues can contribute to reversible bonding and self-repair, while lysine-based surface modification enables sensors or actuation components to be attached. In advanced composites and coatings, both residues support cross-linking strategies for improved adhesion, toughness, and environmental resistance. Overall, tailored cysteine or lysine incorporation expands the functional design space of silk-based biomaterials, enabling new properties that go beyond natural silk and opening opportunities in performance textiles, medicine, and smart engineering systems.

[0684] In another aspect, the present invention relates to a (recombinant / synthetic) silk polypeptide, specifically spider silk polypeptide, attached to / linked to a modified N-terminal tag. This tag has the amino acid sequence MASKTGGQQMG (SEQ ID NO: 39). It, thus, differs from the N-terminal tag MASMTGGQQMG (SEQ ID NO: 30) in that the M (methionine) at position 4 is replaced by K (lysine). This modified N-terminal tag is combined with one or more repeats, specifically 1 to 80 repeats, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80 repeats, of the amino acid sequence according to SEQ ID NO: 1. A preferred spider silk polypeptide having this modified N-terminal tag has the amino acid sequence according to SEQ ID NO: 40.

[0685] In another aspect, the present invention relates to a nucleic acid molecule encoding the silk polypeptide as described above.

[0686] In another aspect, the present invention relates to a method for producing a silk polypeptide comprising the step of:

[0687] (i) expressing the nucleic acid molecule as described above in a cell or synthesizing the nucleic acid molecule of the second aspect in an in vitro transcription / translation system, thereby producing the silk polypeptide.

[0688] In another aspect, the present invention relates to a silk polypeptide multimer comprising at least two silk polypeptides as described above.

[0689] In another aspect, the present invention relates to an article comprising the silk polypeptide as described above or the silk polypeptide multimer as described above.

[0690] In another aspect, the present invention relates to a method for producing an article comprising the steps of:

[0691] (i) providing a solution comprising the silk polypeptide as described above or the silk polypeptide multimer as described above, and

[0692] (ii) forming an article out of / from the solution provided in (i).

[0693] In another aspect, the present invention relates to the use of the silk polypeptide as described above, the silk polypeptide multimer as described above, or the article as described above in the textile industry, cosmetics industry, medical industry, agricultural industry, bioelectronics and for composite materials. The composite materials preferably include fibers, films, foams, gels and particulates. The above (recombinant / synthetic) silk polypeptide is specifically a spider silk polypeptide.

[0694] Various modifications and variations of the invention will be apparent to those skilled in the art without departing from the scope of invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art in the relevant fields are intended to be covered by the present invention.

[0695] EXAMPLES

[0696] The examples given below are for illustrative purposes only and do not limit the invention described above in any way.

[0697] EXAMPLE 1 :

[0698] 1. Spider silk protein preparation:

[0699] The recombinant spider silk protein comprising SEQ ID NO: 3 as reference as well as the different spider silk proteins of the invention comprising [AmB]nwith m = 48 and n = 1, [BAmB]n, with m = 48 or 32 and n = 1, Y-Am, with Y as linker comprising Cys and m = 48, [BAmBA0]n, with m = 16, o = 32, and n = 1, or [AmBAmBAm]n, with m = 16 and n = 1 were prepared as described in WO 2006 / 008163.

[0700] 2, Spider silk protein spinning dope preparation:

[0701] 500 mg of the recombinant spider silk proteins comprising SEQ ID NO: 3 as reference as well as the different spider silk proteins of the invention comprising [AmB]nwith m = 48 and n = 1, [BAmB]n, with m = 48 or 32 and n = 1, Y-Am, with Y as linker comprising Cys and m = 48, [BAmBA0]n, with m = 16, o = 32, and n = 1, or [AmBAmBAm]n, with m = 16 and n = 1 were dissolved in 10 mL of 6 M GdmSCN (5% (w / v)). After recombinant spider silk protein dissolution, insoluble parts were removed by centrifuging (8500 rpm, 30 min, 18°C). The supernatant was dialyzed (MWCO: 6-8 kDa) each time for 4 hours with the following buffers:

[0702] 1) Buffer 1 : 50 mM NH4HCO3 (pH 7.8), 500 mM urea, 500 mM GdmSCN,

[0703] 2) Buffer 2: 50 mM NH4HCO3 (pH 7.8), 500 mM urea, 250 mM GdmSCN, and 3) Buffer 3 : 50 mM NH4HCO3 (pH 7.8), 500 mM urea.

[0704] Subsequently, the recombinant spider silk protein was dialyzed against 20 % (w / v) PEG (35 kDa), 500 mM urea until a concentration of 15% was reached. The spinning dope was then used for spinning.

[0705] 3, Spider silk protein fiber production:

[0706] For wet spinning, spinning dopes comprising the spider silk protein comprising SEQ ID NO: 3 as reference as well as the different spider silk proteins of the invention comprising [AmB]nwith m = 48 and n = 1, [BAmB]n, with m = 48 or 32 and n = 1, Y-Am, with Y as linker comprising Cys and m = 48, [BAmBA0]n, with m = 16, o = 32, and n = 1, or [AmBAmBAm]n, with m = 16 and n = 1 were transferred into a spinneret with a spinning nozzle. The spinning nozzle submerged into a coagulation bath. As coagulation bath, ethanol, butanol, methanol, propanol, polyethylene glycol, or isopropanol was used. The spinning dope was extruded into the coagulation bath. The coagulated fiber was taken out of the coagulation bath and was stretched in a stretching bath. As stretching bath, ethanol, butanol, methanol, propanol, isopropanol, polyethylene glycol, or H2O was used. After stretching, the fiber was taken out of the stretching bath. In order to produce fibers with different shrinkage potential, a coagulated fiber can alternatively be taken out of the coagulation bath without stretching in a stretching bath (e.g. for the use as the first fiber or yam) and another coagulated fiber can be taken out of the coagulation bath and can be stretched in a stretching bath (e.g. for the use as the second fiber or yam).

[0707] 4, Tensile strength measurements

[0708] The fiber from the spider silk protein comprising SEQ ID NO: 3 as reference as well as fibers from the different spider silk proteins of the invention comprising [AmB]nwith m = 48 and n = 1, [BAmB]n, with m = 48 and n = 1, Y-Am, with Y as linker comprising Cys and m = 48, [BAmBA0]n, with m = 16, o = 32, and n = 1, or [AmBAmBAm]n, with m = 16 and n = 1 were mechanically tested, particularly the tensile strength was determined.

[0709] Tensile strength of the different fibers were tested using a Zwick Z0.5 (Zwick Roell) by fastening the ends of a short piece of fiber between two brackets and applying increasing tensile force until the thread tore. The fineness of a fiber is defined as: fineness [tex] = mass of fiber [g] / length of fiber [10 000 m].

[0710] The fineness is then used for defining a characteristic attribute of the fiber: fineness related maximum tensile strength[cN / tex] = maximum tensile strength [cN] / fineness [tex].

[0711] The following results were achieved:

[0712] 9.3 cN / tex, spider silk protein comprising SEQ ID NO: 3

[0713] 14.3 cN / tex, [AmB]nwith m = 48 and n = 1

[0714] 20.3 cN / tex, [BAmB]n, with m = 48 and n = 1

[0715] 17.3 cN / tex, Y-Am, with m = 48, Y as spacer comprising linker molecule containing Cys

[0716] (SEQ ID NO: 6)

[0717] 17.5 cN / tex, [BAmBA0]n, with m = 16, o = 32, and n = 1

[0718] 11 cN / tex. [AmBAmBAm]n, with m = 16 and n = 1

[0719] It could be shown that the spider silk proteins according to the invention have a higher tensile strength than the reference spider silk protein comprising SEQ ID NO: 3.

[0720] EXAMPLE 2:

[0721] The silk polypeptides as mentioned in Table 1 below were produced and spun into fibers as described in Example 1. Table 1 below shows that two terminal cysteines (at both the N- and C-terminus, e.g. silk polypeptide comprising an amino acid sequence according to SEQ ID NO: 27 and SEQ ID NO: 42) in contrast to one terminal cysteine (at the C-terminus) (e.g. silk polypeptide comprising an amino acid sequence according to SEQ ID NO: 26) or no terminal cysteine (e.g. silk polypeptide comprising an amino acid sequence according to SEQ ID NO: 3, reference) lead to fibers having a smaller percentage loss of tensile strength (cN / tex) when comparing dry versus wet conditions.

[0722] Table 1:

[0723] EXAMPLE 3: The silk polypeptides comprising an amino acid sequence according to SEQ ID NO: 34, SEQ ID NO: 38, and SEQ ID NO: 40 were produced and spun into fibers as described in Example 1. While lysine plays a smaller role in disulfide-mediated networking, it opens up a broad range of chemical flexibility and functional expansion in biomaterial applications. For example, the present inventors could show that with glutaraldehyde / glyoxal as crosslinker in the spin dope or in an aqueous solution before spin dope preparation, a higher dope viscosity and molecular weight (MW) have been achieved. In addition, the present inventors could show that with glutaraldehyde as crosslinker after spinning, a molecular weight (MW) increase has been achieved.

Claims

1. CLAIMS1. A silk polypeptide comprising an amino acid sequence according to formula: [AmB]n, [BAm]n,[BAmB]n, [AmBAm]n,[AmBAo]n, [BAmBAo]n, [AmBAoB]n,[AmBAmBAm]n, [BAmBAmB]n, [BAm]nB,Am-Y, Y-Am, Y-Am-Y, or Am-Yn-AmwhereinA stands for an amino acid sequence according to SEQ ID NO: 1, B stands for an amino acid sequence according to SEQ ID NO: 2, m is an integer between and including 1 and 80, o is an integer between and including 1 and 80, n is an integer between and including 1 and 10, andY is a spacer element comprising a linker molecule containing cysteine, under the proviso that if m and o are present, they differ from each other.

2. The silk polypeptide of claim 1, wherein the silk polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 3, SEQ ID NO: 4, and SEQ ID NO: 5.

3. The silk polypeptide of claims 1 or 2, wherein the linker molecule is selected from the group consisting of an amino acid sequence according to SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, and SEQ ID NO: 9.

4. The silk polypeptide of claim 3, wherein the silk polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17.

5. The silk polypeptide of claims 1 or 2, wherein the silk polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 22, SEQ ID NO: 23, SEQ ID NO: 24, and SEQ ID NO: 25.

6. A nucleic acid molecule encoding the silk polypeptide of any one of claims 1 to 5.

7. A method for producing a silk polypeptide comprising the step of:(i) expressing the nucleic acid molecule of claim 6 in a cell or synthesizing the nucleic acid molecule of claim 6 in an in vitro transcription / translation system, thereby producing the silk polypeptide.

8. The method of claim 7, wherein the method further comprises the step of:(ii) isolating the silk polypeptide from the cell or in vitro transcription / translation system.

9. A silk polypeptide multimer comprising at least two silk polypeptides of any one of claims 1 to 5.

10. The silk polypeptide multimer of claim 9, wherein the multimer is a dimer, trimer, or tetramer.

11. The silk polypeptide multimer of claims 9 or 10, wherein the at least two silk polypeptides are connected to each other via a covalent bound.

12. An article comprising the silk polypeptide of any one of claims 1 to 5 or the silk polypeptide multimer of any one of claims 9 to 11.

13. The article of claim 12, wherein the article is a fiber, preferably a fabric comprising the fiber, a yarn, preferably a fabric comprising the yarn, or a film.

14. A method for producing an article comprising the steps of:(i) providing a solution comprising the silk polypeptide of any one of claims 1 to 5 or the silk polypeptide multimer of any one of claims 9 to 11, and(ii) forming an article out of / from the solution provided in (i).

15. The method of claim 14, wherein the article is a fiber or film.

16. The method of claim 15, wherein the fiber is formed by extruding the solution comprising the silk polypeptide or the silk polypeptide multimer.

17. The method of claim 16, wherein the solution comprising the silk polypeptide or the silk polypeptide multimer is extruded into a coagulation bath.

18. The method of claim 17, where the fiber is extended in a subsequent stretching step.

19. The method of any one of claims 15 to 18, wherein the fiber is subsequently spun into a yarn.

20. The method of claim 15, wherein the film is formed by applying, preferably casting, the solution comprising the silk polypeptide or the silk polypeptide multimer.

21. The method of claim 20, wherein the solution comprising the silk polypeptide or the silk polypeptide multimer is applied, preferably casted, onto a support or substrate.

22. Use of the silk polypeptide of any one of claims 1 to 5, the silk polypeptide multimer of any one of claims 9 to 11, or the article of claims 12 or 13 in the textile industry, cosmetics industry, medical industry, agricultural industry, bioelectronics and for composite materials.

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