14 results about "Agarase" patented technology

The application belongs to the technical field of genetic engineering, and discloses a kind of saccharomyces cerevisiae for producing rare ginsenoside by seaweed biomass and a construction method and application thereof.The saccharomyces cerevisiae has the following characteristics: overexpression of agarase, neojuncanohydrolase, hydroxymethylglutaryl coenzyme A reductase, isopentenyl diphosphate delta isomerase, dammaradienol synthase, protopanaxadiol synthase, cytochrome P450 reductase, protopanaxatriol synthase and glycosyltransferase.The application combines enzymolysis of seaweed biomass with fermentation of rare ginsenoside, which not only endows wild-type yeast with the ability to degrade seaweed biomass that it originally does not have, but also effectively improves the yield of squalene and downstream terpenes (rare ginsenoside Rh1) by overexpression of tHMG1 and IDI1.The saccharomyces cerevisiae can effectively utilize seaweed biomass to obtain squalene and rare ginsenoside Rh1, and has the characteristics of simplicity, economy and ecological friendliness, can convert cheap biomass into high-value products, and provides a way for the development of marine bioeconomy.

The present invention relates to a method of producing neoagarotetraose (NA4) and neoagarohexaose (NA6) with high purity in large amounts by liquefaction of the substrate agarose using a thermostable GH16B β-agarase derived from a novel agarolytic bacterium Cellvibrio sp. KY-GH-1 deposited under accession number KCTC 13629BP. The method of producing neoagarotetraose (NA4) and neoagarohexaose (NA6) with high purity in large amounts by liquefaction of the substrate agarose using a thermostable GH16B β-agarase derived from a novel agarolytic bacterium Cellvibrio sp. KY-GH-1 deposited under accession number KCTC 13629BP according to the present invention may effectively produce NA4 and NA6 with high purity in large amounts by efficiently performing liquefaction of the substrate agarose, because the thermostable GH16B β-agarase exhibits excellent enzyme activity at a high temperature equal to or higher than the agarose gelling temperature and has long-term thermal stability even at high temperatures.

The preparation method comprises the following steps: (1) dissolving agar in a citric acid monohydrate solution, and carrying out acidolysis to obtain an acidolysis solution; centrifuging, filtering, adding beta-agarase AgWH50B, and carrying out enzymolysis for 20-28 hours at the temperature of 30-35 DEG C; boiling, centrifuging and filtering to obtain supernate, namely crude oligosaccharide liquid containing agarotriose; (2) dissolving agar in a phosphoric acid solution, and degrading for 55-65 minutes at the temperature of 97-103 DEG C; centrifuging and filtering to obtain supernate, namely crude oligosaccharide liquid containing agarobiose; (3) dissolving agar in deionized water, adding alpha-agarase A33, and carrying out enzymolysis at 38-42 DEG C for 20-28 hours; and boiling, centrifuging and filtering to obtain supernate, namely crude oligosaccharide liquid containing agarotetraose. The preparation method of the agaro-oligosaccharide is used for preparing agarotriose, agarobiose and agarotetraose, and the product purity is high. The method can provide guidance for subsequent large-scale industrial production of agaro-oligosaccharide.

An engineered bacterium based on Bacillus subtilis is provided, a genome of the engineered bacterium includes a multi-enzyme element, and the multi-enzyme element comprises a class I β-agarase element (E1 element), a class II β-agarase element (E2 element), and an α-neoagaro-diohydrolase element (E3 element). The engineered bacterium integrates agarase genes into the Bacillus subtilis genome, achieving cascade catalysis of agarose to produce active oligosaccharides and monosaccharides, thereby utilizing the biological activity of these active oligosaccharides and monosaccharides to treat intestinal inflammation. An engineered biofilm based on Bacillus subtilis is also provided, which includes the engineered bacterium and its secretions. Furthermore, a living material for multi-enzyme display and treatment of intestinal inflammation in mice is also provided, which includes the engineered bacterium or the engineered biofilm.

The application discloses a agarase, an agarase gene, and a preparation method and application, and recombines alpha-agarase gene of agar-decomposing bacterium of Rhodophyta in E.coli engineering bacteria, obtains recombinant E.coli engineering bacteria E.coli BL21-pET28a(+)‑AgaB which can efficiently express the gene, has higher economic value and industrial application prospect, widens resources for mining and application of new enzymes, and the enzyme is a secreted intracellular protein of GH96 family.In addition, by comparing the gene sequence of the enzyme, it is found that the highest similarity of the amino acid sequence of the enzyme with the reported alpha-agarase is only 54.15%.Through enzymatic property research, the optimal reaction temperature is 40 DEG C; the optimal reaction pH is 7; metal ions Ca2+ and Ba2+ promote the activity.

This invention relates to a disaccharide exoglycosidase β-agarase with both galactosidase and β-galactosidase activities and its applications, belonging to the field of biotechnology. This invention discloses for the first time a method for developing a β-agarase from *Pseudomonas alterniflora* (…). Pseudoalteromonas An enzyme, ORF0276, and its encoding gene, possessing both galactosidase and disaccharide exonuclease activities, were obtained from the genome of strain Q02 (sp.). This enzyme exhibits strong thermostability, high pH tolerance, and stable physicochemical properties, thus possessing potential for industrial applications. When degrading agar polysaccharide substrates, it can act on the β-1,4 glycosidic bonds of the sugar chains to produce a product primarily composed of neo-agarbiose, which can be used for the industrial preparation of neo-agarbiose (NA2). This research provides a molecular template and theoretical reference for the discovery of such multi-functional tool enzymes.

The invention provides agarase Ag0139 as well as a fusion enzyme and application thereof, and relates to the technical field of enzyme engineering. The agarase Ag0139 disclosed by the invention can be used as a catalytic degradation agarase, and plays a key role in a green biodegradation process of agarose; and the key technical problem of extremely low solubility of the GH118 family agarase in an escherichia coli expression system is successfully solved through fusion enzyme engineering. According to the constructed fusion enzyme MBP-Ag0139, the soluble high-efficiency expression is realized; according to the constructed fusion enzyme MBP-Ag0139-SpyTag, efficient and stable immobilization of agarase is achieved, the catalytic characteristic and thermal stability of agarase are improved, the number of times of recycling can be effectively increased, and the use cost is reduced. And a solid foundation is laid for green and low-cost enzymatic industrial production of high-polymerization-degree agaro-oligosaccharide.

This invention relates to an endonuclease β-agarase, its mutants, mutation methods, and applications, belonging to the field of biotechnology. This invention discloses for the first time a mutant of *Pseudomonas alterniflora* (…). Pseudoalteromonas An endonuclease β-agarase, ORF2093, was obtained from strain A601. This endonuclease β-agarase ORF2093 exhibits certain thermal stability, wide pH tolerance, and stable physicochemical properties, thus possessing potential for industrial application. This invention employs rational design and site-directed mutagenesis technology to mutate the serine residue at position 373 in the non-catalytic region of the endonuclease β-agarase ORF2093 to asparagine. The resulting mutant showed significantly enhanced relative activity compared to the wild type, and it was found that the mutant enzyme possesses the ability to degrade novel agaroctaose substrates.

Certain embodiments of the present disclosure generally relate to modified agarose polysaccharides for various uses, such as for extracellular matrices, tissue fillers, regenerative implants, tissue scaffolds, wound dressings, or other applications, including biomedical applications. In some aspects, a modified agarose polysaccharide having certain secondary structures, such as a 0-sheet structure, may be reacted with an enzyme such as an agarase, e.g., to reduce its molecular weight or shear modulus, or degrade it, etc. This may be useful, for example, in certain in vivo applications where the modified agarose polysaccharide has been applied to a subject, and it is desired to alter the modified agarose polysaccharide in such a fashion. For example, an agarose implanted into a subject as a tissue filler may be altered by applying an agarase to the implant, which may allow the implant to be altered, reshaped, removed from the subject, etc. Other aspects as discussed herein are generally directed to methods of making or using such altered agaroses, other reactions involving such agarases (e.g., in vitro or in vivo), kits involving such altered agaroses, or the like.

The application belongs to the technical field of biotechnology, and discloses a beta-agarase, a method for preparing the beta-agarase, application and a method for preparing neoaarabinose. The beta-agarase provided by the application specifically includes an amino acid fragment as shown in SEQ ID NO: 1 or a variant fragment with at least 90% sequence identity with the amino acid fragment as shown in SEQ ID NO: 1, which can efficiently and specifically realize degradation of agar oligosaccharide under mild conditions and the degradation product is a single product neoaarabinose, and has the advantages of high enzyme activity, mild reaction, high stability and uniform enzymatic product, and has excellent application prospects in realizing large-scale industrial production of neoaarabinose.

The application provides an agarase AgaCA233, a mutant thereof and application. The application mines a beta-agarase of a GH16 family, named AgaCA233, from Catenovulum agarivorans DS-2 genome information through bioinformatics technology, the enzyme has high catalytic activity and thermal stability, and can be efficiently applied to the production of industrialized preparation of agar oligosaccharide. On the other hand, the gene engineering technology is used to the truncation mutation of the above agarase AgaCA233. The thermal stability and catalytic activity of the agarase AgaCA233 mutant of the application are greatly improved compared with the wild type AgaCA233, and the agarase is one of the most stable GH16 family agarases at present, and can be applied to the enzymatic industrial production of agar oligosaccharide, so as to greatly reduce the production cost of agar oligosaccharide.

The invention discloses a mutant for improving catalytic activity and stability of alpha-agarase, and belongs to the technical field of gene engineering and enzyme engineering. The invention provides an alpha-agarase mutant, which is obtained by mutating the 1396th amino acid of agarase with an amino acid sequence as shown in SEQ ID NO.1. The catalytic activity and the stability of the alpha-agarase mutant S1396T disclosed by the invention are improved compared with those of a wild type enzyme, and the polymerization degree distribution of a product is highly consistent with that of the wild type enzyme; the production efficiency of continuous production of the enzyme in actual industrial application is improved, and the method has a good industrial application prospect.

This invention belongs to the field of air purification technology and discloses an environmentally friendly and efficient in-vehicle formaldehyde removal material, its preparation method, and its application. The in-vehicle formaldehyde removal material, by weight, comprises 5-8 parts of microbial agent and 83-113 parts of matrix material, wherein the matrix material includes 20-30 parts of modified gelatin, 50-60 parts of agar, 6-10 parts of chitosan, and 2-5 parts of agarase. The formaldehyde purification material provided by this invention can rapidly adsorb and decompose formaldehyde into harmless CO2 and H2O. This formaldehyde removal material has strong adsorption capacity, high formaldehyde removal efficiency, good material stability, and low cost, achieving the purpose of continuously and thoroughly removing formaldehyde from the air inside the vehicle.

The invention discloses ZIF-8 immobilized beta-agarase based on lysozyme surface modification and a preparation method of the ZIF-8 immobilized beta-agarase based on lysozyme surface modification, and the method comprises the following steps: using a lysozyme surface modification ZIF-8 carrier to obtain a phase change ZIF-8 carrier; under the mediation of glutaraldehyde, the phase change ZIF-8 carrier and beta-agarase are subjected to covalent crosslinking, and the immobilized beta-agarase is obtained. According to the method, the immobilized beta-agarase of which the protein loading rate and the recovery rate are 45.3% and 71.3% respectively can be obtained; the immobilized beta-agarase has more excellent environmental tolerance, the affinity to a substrate is reduced, but the catalytic activity is greatly improved, and the catalytic rate is greatly increased; 70% of enzyme activity is still maintained during the sixth repetition; the enzyme still has 70% enzyme activity after being placed at 25 DEG C for 25 days, and has excellent performance in the aspects of storage stability and operation repeatability.