13 results about "Ester hydrolase" patented technology

The invention discloses a producing strain of D-pantoic acid lactone hydrolase and application of the producing strain. The producing strain is fusarium moniliforme DPLH6, and the preservation number of the producing strain is CGMCC (China General Microbiological Culture Collection Center) No. 42135. The fusarium moniliforme strain disclosed by the invention has the capability of producing the D-pantoic acid lactone hydrolase at high yield, the D-pantoic acid lactone is prepared after the D-pantoic acid lactone hydrolase fermented by the strain is immobilized by glutaraldehyde, less enzyme dosage and shorter catalysis time can be realized, and the ee value of the target product D-pantoic acid lactone is greater than 99%.

The application relates to the field of genetic engineering, and discloses a 2-hydroxyethyl terephthalate diester hydrolase mutant, a coding gene, a recombination carrier, a recombination strain, an enzyme preparation and application. The 2-hydroxyethyl terephthalate diester hydrolase mutant is obtained by mutating at least one of positions 109, 110, 138, 225, 276, 287, 312, 313, 333, 335, 351, 356, 387, 394, 395, 401 and 413 of an enzyme with the amino acid sequence shown in SEQ ID NO:1. The 2-hydroxyethyl terephthalate diester hydrolase mutant has excellent thermal stability, and has better catalytic efficiency at high temperature.

The invention relates to the technical field of bioengineering, in particular to an ester hydrolase mutant and application thereof. According to the present invention, the screened wild-type ester hydrolase derived from Pseudomonas fluorescens is subjected to mutation to obtain the ester hydrolase mutant, the ester hydrolase mutant is applied to the synthesis of the sitagliptin intermediate, and compared with the wild-type ester hydrolase, the ester hydrolase mutant has characteristics of high enzyme activity and high stereoselectivity on the substrate (compound II), the enzyme consumption is significantly reduced, and the yield of the sitagliptin intermediate is significantly improved; the chiral purity of the reaction product (compound I) is greatly improved, and the method has a good industrial application prospect.

The invention belongs to the field of biotechnology and biocatalysis, and discloses application of ester hydrolase in preparation of beta-keto acid compounds. A new esterase gene is subjected to heterologous overexpression in escherichia coli through a genetic engineering means to obtain a genetically engineered bacterium for efficiently expressing esterase, and the genetically engineered bacterium is obtained by taking escherichia coli as a host and transferring a recombinant plasmid carrying an esterase gene. The engineering bacterium can efficiently express and produce ester hydrolase, has the advantages of strong substrate tolerance, high concentration feeding, high catalytic efficiency, conversion rate of 99% or more, no by-product generation, short reaction period, less biocatalyst dosage, simple and convenient preparation method, mild conditions and environmental friendliness, and has good industrialization prospects.

The present application provides a method for preparing a chiral intermediate of Niraparib by means of a chemical-enzymatic method. The method provided by the present application comprises: subjecting compound II, as a starting material, to a Michael addition reaction to obtain compound III; then, subjecting compound III to enzymatic resolution using an ester hydrolase to obtain chiral compound IV, with an ee value of up to 99%; and finally, subjecting compound IV to cyclization and amide reduction reactions to obtain chiral intermediate I of Niraparib. The route features simple operation and low cost, and can be applied to industrial production.

This invention discloses a composite nanozyme, its preparation method, and its application. The composite nanozyme uses Prussian blue nanoparticles as a carrier, with a phospholipid bilayer formed by dimyristoylphosphatidylcholine coated on the surface of the Prussian blue nanoparticles. The phospholipid bilayer contains (2,3-dioleoyl-propyl)-trimethylamine and undecylimidazole. This invention is the first to disclose a composite nanozyme formed by modifying the surface of Prussian blue nanoparticles with DOTAP and imidazole groups. The obtained composite nanozyme can effectively catalyze ester hydrolysis, producing at least two orders of magnitude acceleration, which provides a possibility for the direct hydrolysis of cholesterol esters in atherosclerotic plaques by nanomedicines. This invention expands the enzyme-like activity of the Prussian blue nanozyme through special modification, providing a solution for simultaneously achieving multifunctional composite nanozymes with ester hydrolytic enzyme function, catalase-like properties, and superoxide dismutase-like properties.

This invention relates to a cyclohexenecarbamate hydrolase mutant, its preparation method, and its applications. The cyclohexenecarbamate hydrolase mutant provided by this invention, when used as a catalyst in the asymmetric resolution of chiral cyclohexenecarbamate to prepare chiral cyclohexenecarboxylic acid, exhibits suitable conversion rates, high optical purity (chiral purity exceeding 99%), mild reaction conditions, environmental friendliness, simple operation, high yield, low cost, and ease of industrial scale-up. Therefore, the cyclohexenecarbamate hydrolase mutant and its gene of this invention have promising prospects for industrial application development.

The invention belongs to the technical field of bioengineering, and particularly relates to a carboxylate hydrolase expression system and application thereof. The carboxylate hydrolase expression system comprises: (A) a polynucleotide sequence encoding carboxylate hydrolase EST; and (B) a polynucleotide sequence for coding a signal peptide, the polynucleotide sequence for coding the signal peptide being selected from any one of SEQ ID No: 2-7; and (C) a secretory carrier. Host cells loaded with the carboxylate hydrolase expression system can directly secrete esterase into a culture medium in the fermentation process, and meanwhile the expression quantity and catalytic activity of the esterase are improved. According to the invention, the fermentation process is also optimized, the expression potential of the carboxylate hydrolase EST is further released, and the industrial production requirements of high selectivity and high conversion rate are met.

Provided in the present invention is a method for preparing sucralose using a biological enzyme, which belongs to the technical field of biocatalysis. The method refers to a method for removing the acetyl group at the 6-position in sucralose-6-acetate in an enzymatic reaction system by controlling enzymatic reaction conditions to obtain a sucralose product. According to the present invention, based on a study on the enzymatic hydrolysis mechanism of sucralose-6-acetate, efficient sucralose-6-acetate hydrolases are selected. The enzyme-to-substrate ratio, reaction temperature, and pH are optimized by reducing the inhibitory effect of reaction substrates and products on the enzyme, thereby greatly improving the hydrolysis efficiency of sucralose-6-acetate. In addition, in the present invention, pure water is used to replace a 0.15 mol / L PBS buffer system, and a 5 L tank is used to achieve repeated use of enzyme over 120 batches, greatly reducing the cost of starting materials. The operation is simple, the reaction is complete, and the industrialized and large-scale production can be easily implemented.

The invention relates to the technical field of enzyme engineering, and discloses a preparation process of acid-adaptive zearalenone lactone hydrolase, which comprises the following steps: providing recombinant escherichia coli containing a gene for coding mutant protein, the mutant protein mutates the 59th alanine into proline and / or mutates the 161st asparagine into phenylalanine based on a wild enzyme; carrying out enlarge culture on the strain, then carrying out induced expression, collecting thalli, breaking walls and separating supernate; and carrying out affinity chromatography purification and elution on the supernate to obtain the hydrolase. By introducing rigid and hydrophobic side chain mutation, the thermodynamic stability and catalytic efficiency of the enzyme are improved, so that the enzyme has excellent acid resistance; by combining optimized expression and purification conditions, efficient preparation of high-activity soluble protein is realized, the problems that an existing enzyme preparation is easy to inactivate and low in yield in an acid environment are solved, and the method is suitable for industrial production of feed additives.

The application discloses a method for flame-retardant finishing of polyester by graft modification, and belongs to the technical field of textile dyeing and finishing. Specifically, first, polyester fabric is treated by means of ester hydrolase to hydrolyze ester bonds on the surface of the polyester fabric to generate hydroxyl groups; then, methacrylic anhydride is reacted with the hydroxyl groups on the surface of the polyester fabric to introduce vinyl groups on the surface of the polyester fiber; finally, the polyester fabric is immersed in a mixed solution of vinyl phosphonic acid and N,N'-methylene bisacrylamide, and graft polymerization is catalyzed by horseradish peroxidase to form a polyvinyl phosphonic acid layer on the surface of the polyester, thereby realizing the method for flame-retardant finishing of the polyester. The specific steps include: (1) ester hydrolase pretreatment of the polyester; (2) introduction of vinyl groups on the surface of the polyester; and (3) graft polymerization catalyzed by horseradish peroxidase. Compared with the traditional baking finishing method, the method has good flame-retardant finishing, and avoids the shortcomings of easy strength decrease of the polyester and high production energy consumption in the traditional high-temperature baking finishing method.

The invention provides a preparation method of efficient immobilized D-pantoic acid lactone hydrolase. The method comprises the following steps: mixing wet thalli of D-pantoic acid lactone hydrolase with a glutaraldehyde aqueous solution, and pre-crosslinking to obtain a thalli suspension; dissolving sodium alginate in water to obtain a sodium alginate aqueous solution; mixing the thallus suspension with a sodium alginate aqueous solution, and performing emulsification and vacuum degassing treatment to obtain an emulsion; dropwise adding the emulsion into solidification liquid containing calcium chloride and a synergistic cross-linking agent, solidifying, collecting immobilized enzyme microspheres, and washing to obtain the efficient immobilized D-pantoic acid lactone hydrolase. The immobilized D-pantoic acid lactone hydrolase is high in mechanical strength and good in enzyme activity stability, can be repeatedly used for more than 500 times, is applied to catalysis of hydrolysis of DL-pantoic acid lactone, and can realize efficient and low-cost green synthesis of D-pantoic acid.