7 results about "Agarase" patented technology

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.

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.

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.