17 results about "Transaldolase" patented technology

The invention provides a construction method and application of recombinant yarrowia lipolytica with high yield of tyrosol, and belongs to the field of bioengineering. The recombinant yarrowia lipolytica with high yield of tyrosol is named as a yarrowia lipolytica XJ-TL strain, and the recombinant yarrowia lipolytica with high yield of tyrosol is named as a yarrowia lipolytica XJ-TL strain. The recombinant yarrowia lipolytica disclosed by the invention expresses an ethanol dehydrogenase encoding gene, and simultaneously expresses any one or a combination of more of a DAHP synthase mutant encoding gene, a chorismate mutase mutant encoding gene, a glucose 6-phosphate dehydrogenase encoding gene, a transketolase encoding gene and a transaldolase encoding gene; meanwhile, a natural promoter of a pyruvate kinase coding gene is truncated. After the recombinant yarrowia lipolytica XJ-TL strain is subjected to fed-batch fermentation, tyrosol can be synthesized at a relatively high level. The construction method of the recombinant yarrowia lipolytica is easy to operate, and efficient synthesis of tyrosol can be achieved.

The present invention discloses a method for synthesizing hydroxytyrosol by multi-enzyme cascade, comprising: 1) preparing a hydroxytyrosol product by using 3,4-dihydroxybenzaldehyde, L-threonine, sodium formate, NAD + As raw material, L-threonine transaldolase, alcohol dehydrogenase, and formate dehydrogenase are used to catalyze the synthesis of L-threo-3-(3,4-dihydroxyphenyl)serine; 2) L-threo-3-(3,4-dihydroxyphenyl)serine is used as substrate, glucose, NAD + Hydroxytyrosol is synthesized through a cascade catalysis of phenylserine dehydratase, α-ketoacid decarboxylase, aldehyde reductase, and glucose dehydrogenase. The synthesis method provided by the present invention achieves a hydroxytyrosol yield of >99% and a space-time yield of 0.88 g / L / h, currently the highest, showing great potential for industrial application and suitable for further promotion and application.

The invention provides a one-step enzymatic synthesis technology of (2S, 3R)-p-methylsulfonyl phenyl serine ethyl ester. Specifically, the invention provides a method for preparing (2S, 3R)-p-methylsulfonyl phenyl serine ethyl ester by a one-step method, and the method comprises the step of obtaining (2S, 3R)-p-methylsulfonyl phenyl serine ethyl ester from p-methylsulfonyl benzaldehyde and L-threonine ethyl ester or a salt thereof under the action of transaldolase in the presence of phosphopyridoxal as a coenzyme.

A method to make tertiary β-hydroxy α-amino acids. The method includes reacting a ketone substrate and a primary or secondary β-hydroxy α-amino acid with an L-threonine aldolase and / or an L-threonine transaldolase for a time, at a temperature, and at a pH wherein the reaction yields a tertiary β-hydroxy α-amino acid product.

The present invention relates to a recombinant microorganism for producing 1,3-propanediol and a method for producing 1,3-propanediol using same. More specifically, the present invention provides a recombinant microorganism having an improved ability to produce 1,3-propanediol through overexpression of a transaldolase-encoding gene (tal), a succinyl-CoA synthetase-encoding gene (sucCD), a cystathionine γ-synthase-encoding gene (metB), an aspartate ammonia lyase-encoding gene(aspA), an aspartate aminotransferase-encoding gene (aspB), or a functional fragment thereof, and a method for producing 1,3-propanediol using same.

The present invention relates to a genetically engineered erythritol strain and a construction method thereof, as well as application of the strain in preparing erythritol by microbial fermentation. The present invention introduces xylose reductase, xylitol dehydrogenase and xylitol kinase into Yarrowia lipolytica to reshape the xylose metabolic pathway, strengthens the expression of transketolase TKL1, transaldolase TAL and erythrose reductase ER in the erythritol bioproduction pathway, reduces the production of byproducts mannitol and arabitol by knocking out mannitol dehydrogenase MDH and arabitol dehydrogenase ArDH, reduces the conversion of erythritol into other substances by knocking out erythritol dehydrogenase EYD, weakens the accumulation of erythritol, strengthens the expression of sugar uptake pathway genes hexokinase HK and transporters Stp1 and Stp2, and finally produces a high-yield erythritol bacterium that can utilize a mixed carbon source of glucose and xylose, with the yield increased from 50.17 g / L to 195.56 g / L. This provides an excellent strain source for the industrial production of erythritol synthesized using xylose as a substrate, and has great industrial application potential.

The present invention belongs to the field of biomedicine, and in particular to a kind of L-threonine transaldolase mutant and its application in the synthesis of chloramphenicol chiral intermediate.The present invention is with 4-nitrobenzaldehyde, L-threonine and sodium formate as substrates, using the co-expression cells of L-threonine transaldolase mutant PmLTTA-Mu4, alcohol dehydrogenase and formate dehydrogenase or its broken liquid as catalyst, under mild conditions (25-35 DEG C, pH6.5-7.5) asymmetric synthesis (2S, 3R)-4-nitrophenylserine.The method can completely convert 5% 4-nitrobenzaldehyde into (2S, 3R)-4-nitrophenylserine in 5h, and space-time yield is up to 15g / L / h, which is the highest level of current (2S, 3R)-4-nitrophenylserine biological synthesis. This synthesis method has mild conditions, simple operation, simple control, a single product configuration, no substrate residue, and a total yield of up to 85%. It has the advantages of high time-space yield, easy purification, and green environmental protection.

The invention relates to the technical field of biochemical engineering, and particularly discloses a recombinant microorganism for producing L-histidine and application of the recombinant microorganism. Compared with an original strain, the recombinant microorganism has the advantages that the expression of a ptsG gene is reduced while galactose transporter protein galP and glucokinase glk are overexpressed, and / or one or more of transketolase tktA, transketolase tktB, transaldolase talA or transaldolase talB are overexpressed, and the original strain is escherichia coli capable of producing histidine. The recombinant microorganism provided by the invention can improve the production efficiency of histidine and reduce the cost of industrial production of histidine.

The invention relates to recombinant escherichia coli with high yield of gadusol and application of the recombinant escherichia coli, and belongs to the technical field of genetic engineering. The method comprises the following steps: firstly, expressing gadusol synthetic pathway related enzymes, namely EEVS and MT-OX, in escherichia coli, and secondly, systematically modifying a metabolic pathway, namely enhancing the expression of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and transketolase 1, and knocking out 6-phosphofructokinase, transaldolase genes and phosphoglycerate kinase genes at the same time. In addition, an efficient circulating system of cofactors SAM and NAD + is also constructed, and 4.2 g / L gadusol is synthesized by recombinant escherichia coli in a 5-L fermentation tank amplification system and is far higher than the highest yield in the prior art. According to the invention, efficient production of the gadusol is realized through engineering transformation of escherichia coli, and a foundation is laid for industrial preparation of the gadusol.

The invention discloses transaldolase and application thereof in preparation of a chloramphenicol intermediate. Compared with the amino acid sequence shown in SEQ ID NO: 1, the transaldolase contains amino acid residue difference at C57 and / or F59 sites, wherein the 57 and 59 positions refer to the amino acid residue number in SEQ ID NO: 1. The transaldolase disclosed by the invention is utilized to catalyze and generate a target product (2S, 3R)-p-nitrobenzene serine by taking p-nitrobenzaldehyde and L-threonine as substrates, the substrate conversion rate is relatively high, and the target product has relatively high stereoselectivity.

The present invention discloses the rational transformation of L-threonine transaldolase and its integrated system for the efficient synthesis of β-hydroxy-α-amino acids, belonging to the field of biocatalytic engineering. The present invention clones the gene of L-threonine transaldolase from Burkholderia diffusa and heterologously expresses it in E.coli BL21 (DE3) to study the enzymatic properties of its recombinant enzyme and the function of catalytic conversion of L-threo-methylsulfonylphenylserine. At the same time, the key amino acid sites of L-threonine transaldolase are mutated to obtain mutants with significantly improved catalytic efficiency and stereoselectivity. The present invention also introduces an L-threonine transaldolase-mediated catalytic system into an efficient by-product acetaldehyde elimination system to construct an integrated system; not only the inhibitory effect of by-products on the catalytic reaction is eliminated, but also the solubility of the substrate is improved by adding the auxiliary substrate isopropanol, while achieving the in situ regeneration of the cofactor NADH required for the reaction.

The invention provides a method for producing in vitro a beta-hydroxy non-standard amino acid (0-OH-nsAA). The in vitro method comprises incubating L-threonine, an aldehyde and an L-threonine transaldolase (TTA). Also provided is a method for producing a beta-hydroxy non-standard amino acid (0-OH-nsAA) by recombinant cells, comprising expressing a heterologous L-threonine transaldolase (TTA) by the recombinant cells, and growing the recombinant cells in a medium. The medium comprises L-threonine and an aldehyde.

The application discloses a Yarrowia lipolytica gene engineering bacterium for producing erythritol by glycerol, and the Yarrowia lipolytica gene engineering bacterium is obtained by random insertion mutation mediated by non-homologous end connection, and strains with high cell growth and high erythritol yield are screened. Further, the gene engineering bacterium overexpresses glycerol dehydrogenase gene GCY3 or ARA1 and dihydroxyacetone kinase gene DAK2 of a glycerol metabolism dihydroxyacetone pathway. Further, the gene engineering bacterium overexpresses transketolase gene TKL1 and transaldolase gene TAL1 of a non-oxidative pentose phosphate pathway. The application further discloses a construction method and application of the gene engineering bacterium. The superior gene engineering bacterium obtained by constructing a mutant library has the characteristics of tolerating high-concentration glycerol, and the substrate conversion rate and glycerol utilization rate are significantly higher than those of a starting strain.

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.

The present invention relates to a biocatalytic process for the production of aroma chemicals. More particularly, the process comprises a transaldolase or transketolase catalyzed conversion of a donor molecule and an acceptor molecule, two identical or different donor molecules, or two identical or different acceptor molecules, thereby obtaining a coupling product. The present invention also provides an aroma composition comprising said coupling product. The present invention further relates to a product supplemented with said coupling product. The present invention further relates to the use of said coupling product as an aroma chemical.

The invention discloses an application of transaldolase TALDO1 in preparation of a medicine for preventing and / or treating Alzheimer's disease, and proposes that TALDO1 is a medicine target of Alzheimer's disease (AD), and the TALDO1 is obviously reduced in the temporal lobe cortex of an AD patient and neurons and synaptic components of a disease model mouse. By improving the expression level of the TALDO1 in hippocampus and cortical neurons, the incubation period of an AD model mouse for finding a platform in a water maze can be shortened, the residence time and path in a target quadrant can be prolonged, the neuron density and the number of dendritic spines in the brain of the AD model mouse can be increased, amyloid plaques are reduced, the AD pathology is improved, and the AD model mouse can be used for preparing a medicine for treating the diseases. It is indicated that by improving the expression level of the neuron TALDO1, AD model mouse learning and memory disorders can be improved, amyloid plaque pathology and neuron degeneration are delayed and controlled, and it is proved that the TALDO1 can be used as a target of drugs for preventing and / or treating AD.

The present invention relates to a recombinant cell. The recombinant cell may express a first enzyme, a second enzyme and a third enzyme and produce a nonstandard amino acid (nsAA). The first enzyme may be a L-threonine transaldolase (L-TTA) or a threonine aldolase (TAs). The second enzyme may be a phenylserine dehydratase or a threonine deaminase (TD). The third enzyme may be an aminotransferase (AT), a L-amino acid dehydrogenase (L-AADH) or a D-amino acid aminotransferase. At least one of the first enzyme, the second enzyme and the third enzyme may be heterologous to the recombinant cell. Also provided are a method for producing a nonstandard amino acid (nsAA) by the recombinant cell and a method for producing a nsAA in a container in the presence of the first enzyme, the second enzyme and the third enzyme.