7 results about "Pyruvate formate lyase" patented technology

The invention discloses a construction method of an escherichia coli mutant for producing succinic acid by fermentation of a synthetic medium. The method comprises the following steps: firstly, knocking out a lactic dehydrogenase gene ldhA, a pyruvate formate lyase gene pflB, a ptsG gene responsible for encoding a phosphotransferase system EIIBC protein, an ethanol dehydrogenase gene adhE, an acetokinase-phosphate transacetylase gene ackA-pta, and a ptsG gene responsible for encoding a phosphotransferase system EIIBC protein in escherichia coli; a phosphoenolpyruvate carboxykinase gene pck from bacillus subtilis is integrated at an SS9 safety site of a strain to obtain escherichia coli ESC6 with high succinic acid yield; and mutating one or more loci in one or more genes of a glucose-transcriptional inhibition factor gene mlc, a nitrate response regulatory factor gene narL and a cyclic adenylate receptor protein gene crp to obtain the escherichia coli mutant capable of producing succinic acid by fermentation of a synthetic culture medium, wherein the one or more loci in one or more genes of the glucose-transcriptional inhibition factor gene mlc, the nitrate response regulatory factor gene narL and the cyclic adenylate receptor protein gene crp are mutated. The strain can be fermented in a synthetic medium to produce succinic acid, so that the fermentation cost is greatly reduced, and the strain has a very wide application prospect.

The invention discloses a recombinant bacterium for producing L-lactic acid through co-utilization of glucose and xylose as well as a construction method and application of the recombinant bacterium. The invention relates to the technical field of biology, in particular to recombinant bacteria for producing L-lactic acid through co-utilization of glucose and xylose as well as a construction method and application. Methylglyoxal synthase, and / or pyruvate formate lyase, and / or fumarate reductase and / or L-lactic dehydrogenase in receptor Escherichia coli Rec1.0 are modified to obtain recombinant Escherichia coli, the recombinant Escherichia coli is fermented for 24 h, L-lactic acid is the only metabolite, and the yield reaches 2458 g / L; the consumption rate of xylose is 0.76 g / g DCW / h, the consumption rate of glucose is 0.69 g / g DCW / h, and the consumption rate of total sugar reaches 1.45 g / g DCW / h. The recombinant Escherichia coli constructed by the invention can realize efficient utilization of lignocellulose hydrolysate (containing glucose and xylose), and has a wide application prospect.

This invention belongs to the fields of fermentation and genetic engineering technology, and provides a high-yield hexanoic acid-producing engineered *Escherichia coli* strain, its construction method, and its applications. This engineered strain is *Escherichia coli*... E. coli w3110 was the starting strain, overexpressing the acetyl-CoA transferase gene. act and β-ketothiolase gene bktB Overexpression of trans-enoyl-CoA reductase gene ter 3-Hydroxybutyryl-CoA dehydrogenase gene hbd, and 3-hydroxybutyryl coenzyme A dehydratase gene crt Or, simultaneously not expressing the pyruvate formate lyase gene. pflB or lactate dehydrogenase gene ldhA This engineered bacteria can convert glucose into hexanoic acid, a high-value product, with a yield of 4.968 g / L after 18 hours of fermentation. It adopts aerobic fermentation, resulting in rapid cell growth, a short fermentation cycle, and a high acid production rate. The fermentation process is simple, easy to control, and has low production costs, which is conducive to its promotion and application in industrial production.

The invention provides recombinant Escherichia coli for synthesizing heme and derivatives thereof, and the recombinant Escherichia coli is used for knocking out genes such as pyruvate oxidase poxB, pyruvate formate lyase pflB and porphyrinoperoxidase yfeX and enhancing genes such as phosphoenolpyruvate carboxylase ppc, glycerol transporter glpF and 3-phosphoglycerol dehydrogenase glpD, so that the heme and the derivatives thereof can be synthesized. After genes such as exogenous 5-aminolevulinic acid synthase hemA and ferrous chelating enzyme hemH are introduced, the heme and the derivatives thereof can be synthesized by taking glycerol as a raw material, and the heme has an application prospect in the field of biological manufacturing.

Recombinant microorganism in which a gene encoding a transcriptional repressor of the glycine cleavage system, pyruvate formate lyase or phosphoglycerate dehydrogenase, is attenuated or deleted from a host microorganism with a formic acid assimilation pathway, a ppsR gene encoding a phosphoenolpyruvate synthase regulatory protein, or a purT gene encoding a phosphoribosylglycinamide formyltransferase, is attenuated or deleted, a gcvTHP gene, consisting of the gcvT gene, the gcvH gene and the gcvP gene, which encodes an enzyme involved in a glycine cleavage system reaction in which host microorganism with the formic acid assimilation pathway is highly expressed, and a gene encoding formate tetrahydrofolate ligase, methenyl tetrahydrofolate cyclohydrolase or methylene tetrahydrofolate dehydrogenase is introduced into the host microorganism via the formic acid assimilation pathway.

The invention discloses an Escherichia coli strain capable of efficiently secreting and expressing alpha-lipoic acid and application of the Escherichia coli strain, and belongs to the technical field of biology. Escherichia coli is used as a chassis strain for synthesizing lipoic acid by a microbiological method, and an efficient production strain is constructed by optimizing a metabolic pathway; the related modification comprises the following steps: overexpressing a lipoic amidase coding gene eflpA, a truncated thioesterase mutant 'TesA coding gene, a lipoyl synthase coding gene lipA, an iron-sulfur cluster regeneration gene cluster coding gene iscSUA, an S-adenosylmethionine synthetase coding gene sam2 and a 5'-methyl adenosine thioate / S-adenosylhomocysteine nucleoside enzyme coding gene mtn, and carrying out gene coding. A fatty acid degrading enzyme coding gene fadE, a thioesterase coding gene tesA, a pyruvate formate lyase gene cluster coding gene pflAB and a glucokinase coding gene glk are knocked out. According to the invention, the Escherichia coli realizes efficient de novo synthesis and secretory expression of lipoic acid, and finally the extracellular yield in the shake flask fermentation process reaches 16.96 mg / L.

This paper discloses the use of modified Escherichia coli and its L-amino acid fermentation production. Specifically, it discloses the use of pyruvate formate lyase, alcohol dehydrogenase, branched-chain amino acid transaminase derived from Escherichia coli, branched-chain amino acid transaminase derived from Bacillus subtilis, thiamine phosphate synthase, and maleate dehydrogenase in the construction of genetically modified bacteria that produce L-amino acids. Experiments have shown that by knocking out the genes encoding pyruvate formate lyase, alcohol dehydrogenase, branched-chain amino acid transaminase derived from Escherichia coli, thiamine phosphate synthase, and maleate dehydrogenase in E. coli capable of producing L-amino acids, and introducing the gene encoding branched-chain amino acid transaminase derived from Bacillus subtilis, recombinant bacteria favorable for L-amino acid accumulation can be obtained. These recombinant bacteria can significantly increase L-amino acid production and reduce costs, which is of great significance in accelerating the industrialization process of L-amino acids.