15 results about "Amidinotransferases" patented technology

Certain C. glutamicum strains overexpress genes coding for enzymes having the function of aspartate-semialdehyde dehydrogenase, aspartate aminotransferase, dihydrodipicolinate synthase, dihydrodipicolinate reductase, diaminopimelate decarboxylase, aspartatokinase and diaminopimelate dehydrogenase. The C. glutamicum strains also express NAD(P)(+) transhydrogenase subunit alpha PntA and NAD(P)(+) transhydrogenase subunit beta PntB of Corynebacterium urealyticum. A method is developed for the fermentative production of L-lysine using such C. glutamicum strains.

An artificial synthesis method for malonyl-CoA and use thereof are provided. By means of heterologous expression of an aminotransferase and a malonyl-CoA reductase, an artificial synthesis pathway for synthesizing malonyl-CoA by using β-alanine (β-ala) as a precursor is constructed as follows: firstly, under catalysis of a transaminase, β-ala transfers amino groups to α-ketonic acid (such as pyruvic acid, oxaloacetic acid, or α-ketoglutaric acid, etc.), to form an intermediate product 3-oxopropanoate and a corresponding amino acid; the 3-oxopropanoate generates malonyl-CoA under the action of the malonyl-CoA reductase. This pathway addresses the defects of the natural malonyl-CoA synthesis pathway, such as low carbon utilization, consumption of energy substance ATP, release of greenhouse gas CO2, and strict regulation of pathway enzymes, a pyruvate dehydrogenase (PDH) and an acetyl-CoA carboxylase (ACC), thereby achieving high yielding of products using malonyl-CoA as a precursor, including flaviolin, octanoic acid, phloroglucinol, pentadecaheptaene, natamycin, and spinosad.

The invention discloses an aminotransferase mutant from thermophilus thermophilus and application of the aminotransferase mutant in production of L-leucine, the activity of the aminotransferase of the mutant is high, the yield of the L-leucine is increased, and meanwhile, accumulation of a byproduct valine is effectively reduced.

The invention relates to the technical field of biosynthesis, and provides a synthesis method of L-2-amino adipic acid-delta-semialdehyde, which comprises the following steps: taking L-lysine and alpha-ketoglutaric acid as substrates, and carrying out transaminase catalytic reaction to obtain L-2-amino adipic acid-delta-semialdehyde; the transaminase is one of L-lysine 6-amino transferase and a mutant of the L-lysine 6-amino transferase; the L-lysine 6-aminotransferase is derived from Stenotrophomonas koreensis, and the amino acid sequence of the L-lysine 6-aminotransferase is as shown in SEQ ID No. 2; the N end and / or C end of the protein limited by SEQ ID No.2 is connected with a label to obtain the fusion protein. According to the technical scheme, the problem of low conversion efficiency of L-2-amino adipic acid-delta-semialdehyde in related technologies is solved.

The present application relates to the technical field of enzyme engineering, and discloses an amino transferase mutant and application thereof.The present application provides a wild-type amino transferase mutant derived from Aspergillus avenaceus.The amino transferase mutant is obtained by carrying out single-point or multi-point combined mutation on the 20th, 60th, 92nd and 186th positions of the amino acid sequence shown in SEQ ID NO.2, and can directly take the sitagliptin intermediate precursor ketone as a substrate, take isopropylamine as an amino donor, take phosphopyridoxyl as a coenzyme, take dimethyl sulfoxide as a substrate solvent, catalyze the preparation of a sitagliptin intermediate with high optical purity, and the specific enzyme activity reaches 139.3 U / g in a reaction system with a final concentration of 50% DMSO, greatly improves the catalytic efficiency, and the product has high stereoselectivity (the e.e. value of the product reaches 99%), and has a wide industrial application prospect.

The invention discloses a mutant of transaminase and application of the mutant. The invention provides a preparation method of a compound II and an aminotransferase mutant. The preparation method of the compound II comprises the following step: in a solvent, in the presence of an aminotransferase mutant, performing an amination reaction as shown in the following formula on a compound I and an amino donor to obtain the compound II. The transaminase mutant provided by the invention has the advantages of good catalytic activity, relatively good heat tolerance and high pH tolerance, and has the advantages of high yield and high stereoselectivity when an R-configuration seven-ring chiral amine compound is obtained through catalysis; wherein the better mutant is higher in stereoselectivity (e.e. Is greater than or equal to 98%) and better in catalytic activity (the conversion rate is greater than or equal to 98%), and the yield of a target product can reach 90% or above. # imgabs0 #

The alanine aminotransferase detection reagent comprises the following components: a buffer solution, magnesium chloride, L-alanine, alpha-ketoglutaric acid, pyruvate oxidase, 4-AAP, a Trinder's reagent, peroxidase, FAD, TPP, an excipient, a stabilizer, a surfactant and a preservative. When the detection reagent is used for detection, the substrate alanine reacts with the alanine aminotransferase to generate pyruvic acid, then the pyruvic acid reacts with the pyruvate oxidase to generate hydrogen peroxide, the generated hydrogen peroxide further oxidizes chromogen pairs, and colored stable quinone compounds are generated through reaction. Compared with a dehydrogenase method, the method disclosed by the invention has the advantages that the linear range is wide, the accuracy and the sensitivity are high, and the repeatability is good; in addition, the excipient selected by the invention can ensure that the reagent has better morphology and remelting solubility when being prepared into the microspheres, and has higher stability.

The present invention discloses an aminotransferase mutant derived from Bacillus megaterium and its application. Wherein, the mutation site of the aminotransferase mutant is selected from one or more of the 59th, 60th, 144th, 161st, 164th, 169th, 174th, 240th, 244th, 327th, 330th, 331st, 373rd, 387th, 410th, 436th, 437th and 442nd positions of the amino acid sequence shown in SEQ ID NO: 1. The aminotransferase mutant of the present invention can catalyze the synthesis of cyclohexanone compounds into trans-aminocyclohexyl compounds, and the yield is greater than 80%, the purity is greater than 98.0%, and the proportion of trans-aminocyclohexyl compounds in the product is greater than 90%, and it has high industrial application value.

The application discloses a high-yield L-homoserine Corynebacterium glutamicum mutant strain and application thereof, and belongs to the technical field of fermentation engineering. The application takes Corynebacterium glutamicum ATCC13032 as a starting strain, knocks out the regulatory protein McbR, amino acid intracellular transport protein MetD, homoserine kinase, phosphoenolpyruvate carboxykinase, cysteine beta cleavage enzyme, O-acetylhomoserine sulfhydrylase, weakens isocitric acid dehydrogenase and dihydrodipicolinic acid synthase, and overexpresses pyruvate carboxylase gene mutant, aspartate kinase mutant, aspartate semialdehyde dehydrogenase, homoserine dehydrogenase, branched-chain amino acid transport protein BrnF, branched-chain amino acid transport protein BrnE, aspartate aminotransferase, bifunctional aspartate kinase / homoserine dehydrogenase 1 mutant, NADP + dependent glycerol-3-phosphate dehydrogenase. The recombinant bacteria provided by the application can reach 63.5g / L of L-homoserine yield after 96h of culture in a fermenter.

The invention provides an aminotransferase and an application of the aminotransferase in preparation of a chiral cyclic amide compound. The invention specifically provides an aminotransferase mutant, and compared with an amino acid sequence as shown in SEQ ID NO: 1, the aminotransferase mutant contains the difference of amino acid residues at one or more sites. The aminotransferase provided by the invention is high in catalytic yield, good in selectivity and good in application prospect.

The present invention relates to a method for producing malonic acid by Saccharomyces cerevisiae through the alanine pathway, belonging to the field of bioengineering. In the present invention, Saccharomyces cerevisiae is used as the starting strain, and the aspartate decarboxylase gene (PAND) from Tribolium castaneum and the β-alanine pyruvate aminotransferase gene (BAPAT) from Bacillus cereus are integrated into the delta site of the Saccharomyces cerevisiae BY4741 genome to construct a malonic acid synthesis pathway in Saccharomyces cerevisiae, and the promoters of cytoplasmic aspartate aminotransferase and succinic semialdehyde dehydrogenase upstream and downstream of this pathway are replaced with strong constitutive promoters to further increase the malonic acid yield. This application provides a new route for the synthesis of malonic acid in Saccharomyces cerevisiae host. After shake flask fermentation of the recombinant Saccharomyces cerevisiae, the malonic acid yield is 4.4 mg / L, and in a 5-L fermenter, the highest malonic acid yield is 44.31 mg / L.

The present invention discloses a kit for detecting mitochondrial isozymes of aspartate aminotransferase and a preparation method thereof. The detection kit comprises a cytoplasmic aspartate aminotransferase-specific adsorption membrane, a first reagent, a second reagent and a third reagent. The structure of the cytoplasmic aspartate aminotransferase-specific adsorption membrane is that acrylic gel-type anion exchange resin particles are sandwiched in the middle region of two layers of cellulose acetate membranes. The first reagent comprises an alkaline reagent. The present invention removes c-AST in a sample to be tested by adding a cytoplasmic aspartate aminotransferase-specific adsorption membrane to the kit, eliminates interference in determination, and simultaneously removes L-aspartic acid and α-ketoglutaric acid originally present in the sample to be tested, thereby reducing background value and improving detection accuracy.

The invention relates to the technical field of enzyme engineering, and discloses an aminotransferase mutant and application thereof. The invention provides a wild type amino transferase mutant which is derived from Aspergillus avenaceus (Aspergillus avenaceus), and a preparation method of the amino transferase mutant. The amino transferase mutant is obtained by carrying out single-site or multi-site combined mutation on the 20th site, the 60th site, the 92nd site and the 186th site of an amino acid sequence as shown in SEQ ID NO.2. As a biocatalyst, sitagliptin intermediate precursor ketone can be directly used as a substrate, isopropylamine is used as an amino donor, pyridoxal phosphate is used as a coenzyme, dimethyl sulfoxide is used as a substrate cosolvent, and the amino transferase mutant is obtained by carrying out single-site or multi-site combined mutation on the 20th site, the 60th site, the 92nd site and the 186th site of the amino acid sequence as shown in SEQ ID NO.2. The Sitagliptin intermediate with high optical purity is prepared through catalysis, the specific enzyme activity reaches 139.3 U / g in a reaction system with the DMSO volume final concentration being 50%, the catalysis efficiency is greatly improved, and the product has high stereoselectivity (the e.e. Value of the product reaches 99%) and has wide industrial application prospects.

The application relates to the field of biological medicine, and discloses a use of indole-3-propionic acid in preparation of a medicine for preventing and treating acute-on-chronic liver failure. Experiments prove that the indole-3-propionic acid can effectively inhibit the formation of neutrophil-related extracellular traps, reduce the levels of alanine aminotransferase, aspartate aminotransferase, total bilirubin and inflammatory factors TNF-alpha, IL-6 and IL-1beta related to acute-on-chronic liver failure, reduce liver tissue necrosis and inflammatory infiltration, and improve the survival rate. Therefore, the indole-3-propionic acid can be used for preparing a medicine for preventing and / or treating acute-on-chronic liver failure, and provides a new small-molecule intervention strategy for acute-on-chronic liver failure.

The present disclosure relates to methods and materials for the production of resveratrol in yeasts (e.g., yeast of the Saccharomyces genus such as S. cerevisiae) by increasing expression of genes of the pentose phosphate or Shikimate pathway and others, such genes, for example, encoding acetyl-CoA synthase, transketolase, transaldolase, enolase, aromatic aminotransferase, prephenate dehydratase, ribose-5-phosphate isomerase, or a monocarboxylate permease.