32 results about "Short-chain dehydrogenase" patented technology

The invention provides short-chain dehydrogenase obtained from Empedobacter brevis, a gene of the short-chain dehydrogenase, recombinant short-chain dehydrogenase, a recombinant expression vector with the gene, a genetically engineered bacterium, a preparation method of the recombinant short-chain dehydrogenase and application of the short-chain dehydrogenase or the genetically engineered bacterium containing the short-chain dehydrogenase to asymmetric reduction of prochiral ketones for preparation of optical pure chiral alcohols. The short-chain dehydrogenase for preparation of the chiral alcohols by asymmetric reduction has remarkable advantages and can be used for synthesis of high-optical-purity chiral alcohols (ee>99%). Moreover, easiness in preparation of catalysts, mild reaction conditions, high substrate adaptability and environment friendliness are realized, asymmetric reduction of the prochiral ketones can be efficiently catalyzed by recombinant cells in an isopropanol-containing reaction system without any coenzymes, and industrial application and development prospect is promising.

The invention discloses a short-chain dehydrogenase CPE (Cytopathic Effect) gene, a gene coding enzyme, a carrier, a recombination engineering bacteria and an application of the engine coding enzyme in an asymmetric reductive carbonylation compound. The short-chain dehydrogenase CPE has relatively high conversion rate and e.e. value; and the reductase with relatively low Km value can keep enzyme activity for a longer time under a condition that the concentration of substrate is relatively low; and the quantity of added enzyme can be reduced in the actual industrial production; and the cost can also be reduced; and moreover, the maximum reaction speed can be reached when the substrate with low concentration is added, so that the production period of unit weight products can be reduced in the actual industrial production, and the energy consumption and the labor cost can be decreased.

The invention discloses a nested PCR (polymerase chain reaction) kit for detecting duck-manure pollution in a water body and a detection method thereof, and belongs to the field of the detection of pollution in water bodies. The nested PCR kit for detecting the duck-manure pollution in the water body comprises two pairs of nested PCR primers, dNTP (deoxyribonucleoside triphosphate), a PCR buffer, a Taq polymerase, a Mg<2+> solution and ddH2O (double distilled water). Two rounds of PCR amplification are used by a nested PCR method. The detection method comprises the following steps of extracting a DNA (deoxyribonucleic acid) in a to-be-detected water sample, and carrying out a first round of PCR amplification by using the DNA in the to-be-detected water sample as a template, wherein the primers are an SDF (stroma derived factor) and SDR (short-chain dehydrogenase / reductase); after a first reaction is terminated, carrying out a second round of PCR amplification by using a product of the first round of PCR amplification as a template, wherein the primers are an NDF (neutral detergent fiber)and NDR, and after a second reaction is terminated, detecting the existence of a 158bp strip, which shows that the water body is subjected to the duck-manure pollution, through agarose gel electrophoresis. According to the method, the detection sensitivity is greatly increased through nested PCR amplification; a little duck-manure pollution which exists in water can be detected; moreover, the method has a favorable specificity, and can be directly applied to the detection and the preventive treatment work of fecal pollution in the water body.

The invention belongs to the technical field of biology, and relates to short-chain dehydrogenase and a mutant thereof, and preparation and applications of a gene, specifically to a wild type C=C double bond reductase OYE1 derived from Saccharomyces pastoris, and a mutant thereof, short-chain dehydrogenases LfSDR1, BmSDR5 and BsSDR8 respectively derived from Lactobacillus fermentum, Bacillus megaterium and Bacillus subtilis, mutants thereof, C=C double bond reductase and C=O double bond reductase with stereoselectivity complementation, genes of C=C double bond reductase and C=O double bond reductase, construction and preparation of a recombinant expression vector containing the gene, expression of recombinase, an enzyme catalytic two-step asymmetric reduction reaction of carvone, the conditions of the reaction, and a detection method of the product dihydrocarveol. Compared with the existing chemical method, the method of the invention has the advantages of being easy to operate, mild in reaction condition, environmentally friendly and the like.

The invention discloses a biological preparation method of a chiral hydroxy acid ester. The method comprises the following steps: (1) oxidizing a fatty acid by ketolase spheroidene monooxygenase to generate a 4-oxo fatty acid; and (2) asymmetrically reducing the 4-oxo fatty acid by short-chain dehydrogenase PpYSDR-M85Q / L136A to obtain an R-hydroxy acid ester. In the biological preparation method of a chiral hydroxy acid ester of the invention, a short-chain dehydrogenase mutant is constructed, the short-chain dehydrogenase mutant greatly improves the activity and chiral selectivity for keto acids compared with the wild type, the efficiency of the enzyme in catalyzing keto acids to prepare chiral lactones can be improved, and thereby an application value of the enzyme is fully explored. Atthe same time, the enzymatic synthesis of the chiral hydroxy acid ester has the characteristics such as simple process, environmental friendliness, and high benefit.

The invention discloses a leifsonia xyli HSO904-based short chain dehydrogenase, and an encoding gene, a carrier, engineering bacteria and application thereof. A gene of the leifsonia xyli HSO904-based short chain dehydrogenase has more than 90% of homology of a nucleotide sequence shown in SEQ ID NO. 1. A colon bacillus BL21 / pET28a (+)-SDR prepared by the recombination of the short chain dehydrogenase is used as an enzyme source, 3, 5-bis-trifluoro methyl acetophenone, trifluoromethyl acetophenone, 4-hydroxyl-2-butanone, acetoacetic ester, 4-chloro ethyl acetoacetate, acetoacetic acid tert-butyl acetate and the like are used as substrates to prepare corresponding chiral compounds such as (R)-3, 5-bis-trifluoromethyl phenethyl alcohol, trifluoromethyl benzaldehyde ethanol, 2-hydroxyl-butyl alcohol, 3-hydroxy ethyl butyrate, 4-chloro-3-hydroxy ethyl butyrate and 3-hydroxy butyric acid tert-butyl acetate through a catalytic asymmetric reduction reaction.

The invention relates to short-chain dehydrogenase FribC capable of hydrolyzing ribose and a variety of fluorinated ribose and application thereof. The short-chain dehydrogenase is characterized in that a coding gene of the dehydrogenase is a gene sequence shown in a sequence 1 or an amino acid sequence shown in a sequence 2; a substrate of the dehydrogenase is D-ribose or modified D-ribose, and the modified D-ribose comprises 5-fluoro-5-deoxy-D-ribose, 4-difluoromethyl-5-deoxy-D-ribose or 4-trifluoromethyl-5-deoxy-D-ribose. The FribC provided by the invention can be prepared into a biocatalyst and is applied to the biotransformation of a variety of ribose; the FribC can also be prepared into a radiotracer used for positron emission tomography (PET).

The invention provides a method for preparing a key chiral intermediate of calcipotriol based on short-chain carbonyl reductase, which comprises the following steps: constructing a first genetically engineered bacterium for expressing CBR54 by using short-chain dehydrogenase SR03 of underground neosphingobium; the method comprises the following steps: performing separation, purification and culture on a first genetically engineered bacterium for expressing CBR54 to obtain a second genetically engineered bacterium for expressing short-chain carbonyl reductase, performing freeze drying on the second genetically engineered bacterium to obtain CBR54 crude enzyme powder, taking the CBR54 crude enzyme powder, GDH enzyme powder and NADH coenzyme as catalysts, taking cyclopropylcarbonyl methyl-benzothiazole-2-thioether as a substrate, adding a buffer solution, performing catalytic reaction for 8-24 hours, and performing separation and purification to obtain the short-chain carbonyl reductase. 2-[(S)-2-hydroxy-2-cyclopropyl)-1-ethylthio]-benzothiazole is obtained, and the calcipotriol key chiral intermediate is obtained; the method can solve the technical problems of high cost, large substrate loss and low product purity of the existing chiral body preparation.

The invention belongs to the field of biotechnology, relates to short-chain dehydrogenase and its mutants and applications, in particular to stereoselective complementary short-chain dehydrogenase mutants, and the mutants are excavated from Lactobacillus fermentum The wild-type short-chain dehydrogenase (LfSDR1) mutation obtained, specifically relates to the short-chain dehydrogenase mutant and its preparation method and its use as a catalyst to catalyze the asymmetric reduction of 4R / S-carvone to prepare stereodiversity carveol. Compared with the existing chemical methods, the method has the advantages of simple operation, mild reaction conditions, and environmental friendliness.

The invention belongs to the field of biotechnology, and discloses a short-chain dehydrogenase gene, a short-chain dehydrogenase BsSDR10, and an engineered bacteria excavated from Bacillus subtilis (Bacillus subtilis). Carbonyl compounds to prepare optically active chiral alcohols. The enzyme has the advantages of stereospecificity, mild reaction conditions and simple operation, and has a good application prospect in the production of chiral pharmaceutical intermediates.

The invention relates to the technical field of biology, in particular to short-chain dehydrogenase mutants and application thereof, wherein the mutants are obtained by mutating wild types of various short-chain dehydrogenase. The invention particularly relates to the short-chain dehydrogenase mutant, a preparation method thereof and a method for preparing a phenethyl alcohol derivative with optical activity through reduction of an acetophenone derivative compound by using the short-chain dehydrogenase mutant.

The invention provides a short-chain dehydrogenase and a gene thereof, a recombinant short-chain dehydrogenase, a recombinant expression vector containing the gene, a genetically engineered bacterium, a preparation method of the recombinant short-chain dehydrogenase, and an application of the short-chain dehydrogenase or the genetically engineered bacterium containing the short-chain dehydrogenase in astaxanthin chiral intermediate synthesis through asymmetric reduction for prochiral ketones. In the application provided by the invention, asymmetric reduction preparation of the short-chain dehydrogenase for chiral alcohols has remarkable advantages, and an astaxanthin chiral intermediate (having an enantiomeric excess (ee) of greater than 99%) with a high optical purity can be synthesised. A catalyst is easy to prepare, the reaction conditions are moderate, a substrate is wide in adaptability, and the short-chain dehydrogenase is environment-friendly; and moreover, the recombinant cell of the short-chain dehydrogenase is capable of efficiently catalyzing the asymmetric reduction for prochiral ketones in an isopropanol-containing reaction system without any coenzyme, and has a great industrialized application and development prospect.

The present invention relates to the field of biotechnology, and relates to short-chain dehydrogenase mutants and applications thereof. Such mutants are obtained through mutation from wild-type short-chain dehydrogenases, and specifically relate to short-chain dehydrogenase mutants and The preparation method thereof and the method for preparing optically active phenethyl alcohol derivatives by utilizing short-chain dehydrogenase mutants through the reduction of acetophenone derivative compounds.

The invention discloses functions and application of a short chain dehydrogenase TsrU. Specifically, the short chain dehydrogenase TsrU can catalyze the carbonyl chiral single reduction reaction of 4-acetyl-2-quinolinic acid or its analogues, can be used for in-vitro efficient production of 4-(1-hydroxymethyl)-2-quinolinic acid or its structural analogues, and in a side chain reaction of thiostrepton biosynthesis, the enzyme has a high tolerance to a substrate, so that the short chain dehydrogenase TsrU can be widely applied to chiral reduction reactions of other similar substrates.