47 results about "Peptide backbone" patented technology

A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker.

Disclosed are beta -peptides containing cylcoalkyl, cycloalkenyl, and heterocylic substituents which encompass the alpha and beta carbons of the peptide backbone. The beta -peptides adopt stable helical and sheet structures in both the solid state and in solution. Method of generating combinatorial libraries of peptides containing beta -peptide residues and the libraries formed thereby are disclosed.

The present invention provides for novel reagents whose fluorescence increases in the presence of particular proteases. The reagents comprise a characteristically folded peptide backbone each end of which is conjugated to a fluorophore. When the folded peptide is cleaved, as by digestion with a protease, the fluorophores provide a high intensity fluorescent signal at a visible wavelength. Because of their high fluorescence signal in the visible wavelengths, these protease indicators are particularly well suited for detection of protease activity in biological samples, in particular in frozen tissue sections. Thus this invention also provides for methods of detecting protease activity in situ in frozen sections.

The invention provides a new compound and a preparation method and application thereof. The structure of the compound provided by the invention is shown as a formula (1). Four-potential hydroxyl of glycosyl on benzyl hydroxyl of peptide framework six-potential amino acid of the compound serves as an axial bond and the compound is obtained by fermentation and has the collection number of China General Microbiological Culture Collection Center (CGMCC) No.3053. The compound provided by the invention has high antibiotic activity, so that the compound plays a very important role in developing a new antibacterial medicament.

Compounds useful as fluorescent or colored dyes are disclosed. The compounds have the following structure (I), including stereoisomers, salts and tautomers thereof, wherein R¹, R², R³, L¹, L², L³, L⁴, L⁵, M, m and n are as defined herein. Methods associated with preparation and use of such compounds are also provided.

The present invention provides cloning sequencing, analyzing, function research of a biosynthesis gene cluster of an antibiotic-Azinomycin B having antitumor activity produced by streptomyces, and its application. The whole gene cluster includes 34 genes: one repeatedly using I type polyketide synthase gene; two naphthalene ring modification enzyme genes; 8 non-ribosomal polypeptide skeleton synthesis and modification enzyme genes; 11 non-natural amino acid structure unit synthase genes; 1 resistance gene; 3 post modification enzyme genes and 8 genes which functions are not determined. The genetic operation of the biosynthesis gene breaks the synthesis of Azinomycin B; the precursor compound is produced by the heterologous expression of synthesis gene and modification gene of naphthalene ring. The gene of the invention and the protein can be used for searching and finding compound or gene, protein applied in medical, industry or agriculture.

A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker.

Disclosed are cyclosporin analogs having amino acid residue substitutions at positions 1, 3, or 7 of the cyclosporin peptide backbone. Also disclosed are conjugates of these cyclosporin analogs in which an HIV protease inhibitor moiety is conjugated to the position-7 amino acid residue of the cyclosporin. These compounds simultaneously bind to and inhibit cyclophilin and HIV protease. The compounds have good bioavailability and potent HIV inhibitory activity. They are useful in the treatment and prevention of HIV-mediated disorders, including AIDS.

The subject matter of the present invention is a cyclic or linear tetra- or pentapeptide binding to somatostatin receptors. The compounds of the invention are characterised in that they contain the radical of an amino carboxylic acid bearing a five-membered ring in the peptide backbone which may optionally contain O, S, Se, N, or P. These compounds are easy to prepare and display increased stability against peptidases. The compounds of the present invention induce apoptosis of tumour cells and the use of said compounds for cancer therapy is described. In particular, the compounds are characterised in that they are active even against tumour cells displaying resistance against other somatostatin derivatives such as octreotide. In addition, the use of the compounds of the invention for tumour diagnosis by means of positron-emission tomography is described, as well as their use as agents against neurogenic inflammation.

The present invention provides for novel reagents whose fluorescence increases in the presence of particular proteases. The reagents comprise a characteristically folded peptide backbone conjugated to two fluorophores such that the fluorophores are located opposite sides of a cleavage site. When the folded peptide is cleaved, as by digestion with a protease, the fluorophores provide a high intensity fluorescent signal at a visible wavelength. Because of their high specificity and their high fluorescence signal in the visible wavelengths, these protease indicators are particularly well suited for detection of protease activity in biological samples, in particular in frozen tissue sections. Thus this invention also provides for methods of detecting protease activity in situ in frozen sections.

Provided are methods for linking polypeptides (including peptides and proteins) to other moieties using radical imitated thiol-ene chemistries, for example, modifying a polypeptide by introducing reactive thiol groups and reacting the thiol groups with olefin-containing reagents or alkyne-containing reagents under conditions that support radical thiol-ene or thiol-yne reactions. The reactive thiol groups have greater activity for radical thiol-ene reactions that a cysteine thiol group, including thiol groups that are separated from the peptide backbone by at least two carbon atoms, for example, the thiol group of a homocysteine residue. Also provided are compositions and biomaterials containing the linked polypeptides, for example, peptide and protein conjugates, and thiol-ene based biocompatible hydrogel polymers, and their uses in the medical field.

Disclosed are beta-amino acid monomers containing cylcoalkyl, cycloalkenyl, and heterocylic substituents which encompass the alpha and beta carbons of the peptide backbone and beta-polypeptides made from such monomers. Method of generating combinatorial libraries of polypeptides containing the beta-peptide residues and libraries formed thereby are disclosed.

Peptide is disclosed which comprises D-enantiomers of amino acids and is capable of interacting with other β-strand structure to form β-sheet, wherein said peptide is selectively Nα-substituted in one edge (first) of the β-strand-forming section of said peptide while the other edge (second) in the opposite orientation to the first edge in view of peptide backbone plane remains Nα-unsubstituted. Such the Nα-substituted peptide is capable of preventing association of said peptide with other β-strand (target) but permits interaction of said peptide with target β-strand in separate peptide-containing molecules through the Nα-unsubstituted edge. The peptide is useful for preventing β-strand association or aggregation.

This invention is intended to identify a gene cluster involved in biosynthesis of a cyclic peptide compound produced by a filamentous fungus of the Curvularia species and to establish a system for synthesizing such cyclic peptide compound. The gene is composed of a first module to a tenth module and encodes a protein having activity of synthesizing a nonribosomal peptide constituting a basic peptide backbone of a cyclic peptide compound produced by a filamentous fungus of the Curvularia species.

A method for increasing the relaxivity of a contrast agent having a metal ion complexed to a chelator is disclosed. The metal ion complex is tethered to the remainder of the molecule by at least two points of attachment such that local motion is limited and higher relaxivity can be achieved. In one non-limiting example version of the invention, the alanine analogue of Gd(DOTA), Gd(DOTAla) wherein Gd is gadolinium and DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid was integrated into polypeptide structures. This resulted in very rigid attachment of the metal ion complex to the peptide backbone. Rigid molecular structures provide fewer degrees of rotational freedom, resulting in greater control over the rotational dynamics and resultant relaxivity. In the case of Gd(DOTAla), the metal complex is tethered to the peptide via the amino acid side chain to the DOTA moiety and via a dative bond from an amide oxygen to the Gd(III) ion.

A mimic of an anti-angiogenic peptide is combined with a self-assembling peptide hydrogel to provide improved treatment for pathological neovascularization management. Pathological neovascularization may cause or worsen intraocular posterior segment diseases, such as diabetic retinopathy (DR) and wet age-related macular degeneration (wet AMD). The attachment of a therapeutic anti-angiogenic motif to a fibrillizing peptide backbone that undergoes nanofibrous self-assembly into an injectable hydrogel was found beneficial for the treatment of aberrant neovascularization. The peptide persists for extended periods in a target site for prolonging the therapeutic timeframe. This injectable hydrogel therapy may unlock potential clinical routes for treating many neovascular diseases.

The present invention provides a method for specifically cleaving a Cα-C bond of a peptide backbone and/or a side chain of a protein and a peptide, and a method for determining amino acid sequences of protein and peptide. A method for specifically cleaving a Cα-C bond of a peptide backbone and/or a side chain bond of a protein or a peptide, comprising irradiating a protein or a peptide with laser light in the presence of at least one hydroxynitrobenzoic acid selected from the group consisting of 3-hydroxy-2-nitrobenzoic acid, 4-hydroxy-3-nitrobenzoic acid, 5-hydroxy-2-nitrobenzoic acid, 3-hydroxy-5-nitrobenzoic acid, and 4-hydroxy-2-nitrobenzoic acid. A method for determining an amino acid sequence of a protein or a peptide, comprising irradiating a protein or a peptide with laser light in the presence of the above specific hydroxynitrobenzoic acid to specifically cleave a Cα-C bond of a peptide backbone and/or a side chain bond, and analyzing generated fragment ions by mass spectrometry.

The invention discloses a pH-responsive non-helix-helix transition antibacterial polypeptide and a preparation method thereof. The method uses glutamic acid, an essential amino acid with biocompatibility, as a raw material, combined with the click chemistry method, to obtain a cationic polypeptide with a helical structure, which is prepared by modifying half of the maleic anhydride derivative through the side chain of the cationic polypeptide with a helical structure. The pH-responsive non-helical-helical transition antibacterial polypeptide has simple process, convenient operation and low cost, and can efficiently realize the secondary structure transformation under specific pH conditions, effectively reduce the biotoxicity of cationic polypeptides, and improve the bioavailability of cationic polypeptides Spend. In the present invention, through the modification of acid anhydrides with different pH responses, non-helical-helical transition antibacterial polypeptides with different pH conditions can be obtained, and the transformation from a low-activity non-helical structure to a high-activity helical structure can be realized under different physiological conditions. The conversion of cationic peptides can kill bacteria at the site of infection, which has broad application prospects.