17 results about "Serine hydroxymethyltransferase" patented technology

The invention discloses a serine hydroxymethyltransferase mutant and an application thereof in production of L-serin.The serine hydroxymethyltransferase mutant with the specific enzyme activity remarkably improved is obtained by conducting saturated mutation on serine hydroxymethyltransferase from escherichia coli and conducting screening, and the serine hydroxymethyltransferase mutant is applied to synthesis of L-serine. The serine hydroxymethyltransferase disclosed by the invention can be used for effectively improving the efficiency of catalyzing glycine and formaldehyde to synthesize L-serine by using the serine hydroxymethyltransferase, reducing the enzyme dosage, remarkably reducing the production cost and reducing the separation difficulty of downstream products.

The present invention relates to an Escherichia coli that efficiently produces 5'-inosinic acid and its application, belonging to the field of bioengineering technology. In order to reduce the degradation of 5'-inosinic acid in Escherichia coli, four phosphatase encoding genes were knocked out using the CRISPR / Cas9 system, and it was found that knocking out the UMP phosphatase encoding gene nagD and the 5'-nucleotidase encoding gene ushA respectively can increase the production of 5'-inosinic acid. Subsequently, in order to inhibit the further conversion of 5'-inosinic acid into guanylate and adenylate, the 5'-inosinic acid dehydrogenase encoding gene guaB was knocked out alone. Finally, in order to enhance the supply and utilization of formyltetrahydrofolate required in the purine synthesis process, the promoter of the serine hydroxymethyltransferase encoding gene glyA was replaced with P tac The recombinant Escherichia coli produced 2113.12 mg / L of 5'-inosinic acid in 48 hours of fermentation, and no antibiotics were required during the fermentation process, indicating that the product has broad application prospects.

The present disclosure provides methods for treating cancer using ferroptosis inducers in combination with one-carbon metabolism inhibitors. The combination of ferroptosis inducers and one-carbon metabolism inhibitors induce greater ferroptosis than treatment with either alone. In certain embodiments, the one-carbon metabolism inhibitors are serine hydroxymethyltransferase (SHMT) inhibitors and / or methylenetetrahydrofolate dehydrogenase (MTHFD) inhibitors. By way of example, the ferroptosis inducers are GPX4 inhibitors.

The present invention relates to a genetically engineered microorganism expressing (i) formate tetrahydrofolate (THF) ligase, methenyi-THF cyclohydrolase and methylene-THF dehydrogenase, (ii) the enzymes of the glycine cleavage system (GCS), (iii) serine deaminase and serine hydroxymethyltransferase (SHMT), (iv) an enzyme increasing the availability of NADPH, and (v) optionally formate dehydrogenase (FDH), and wherein the genetically engineered microorganism has been genetically engineered to express at least one of the enzymes of (i) to (v), wheren said enzyme is not expressed by the corresponding microorganism that has been used to prepare the genetically engineered microorganism, and wherein the enzymes of (i) to (v) are genomically expressed.

The invention belongs to the technical field of biology, and particularly relates to a serine hydroxymethyltransferase mutant and application thereof. Compared with a wild type serine hydroxymethyltransferase mutant, the serine hydroxymethyltransferase mutant has the advantage that the enzyme activity is obviously improved, so that the mutant or a cell containing the mutant can improve the yield and / or the yield of L-serine.

The present invention provides an isolated mammalian cell comprising reduced or eliminated expression of serine hydroxymethyltransferase 2 (SHMT2). Further provided are methods for making such cells and methods related to using such cells for the production of recombinant proteins.

The invention discloses a bacillus licheniformis recombinant strain with high yield of L-cysteine, and belongs to the technical field of synthetic biology and microbial metabolism engineering. The cysteine synthesis flux is enhanced through multiple knockout and combined overexpression. An efficient engineering strain is constructed by knocking out a serine hydroxymethyltransferase coding gene glyA and an L-serine ammonolysis enzyme coding gene sdaAA of a serine catabolism key pathway, knocking out a cysteine catabolism gene metC and combining gene overexpression to introduce a feedback inhibition removal mutant cysEf and a transporter eamA, and the efficient engineering strain is used for preparing a recombinant strain. Finally, the yield of the L-cysteine reaches 1.075 g / L in shake flask fermentation (the conversion rate is 18.69%), and the application potential of the bacillus licheniformis in sulfur metabolism engineering is highlighted.

The invention relates to the technical field of biochemical engineering, and particularly discloses a recombinant microorganism and application thereof in fermentation production of L-histidine. Compared with an original strain, the recombinant microorganism provided by the invention has the advantages that serine hydroxymethyltransferase glyA is overexpressed, and / or glycine cleavage proteins gcvP, gcvT and gcvH 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 L-histidine, and provides a novel efficient method for synthesizing L-histidine by a biological method.

The invention relates to an application of glyA-coded serine hydroxymethyltransferase in preparation of L-serine, in particular to an application of glyA-coded serine hydroxymethyltransferase in preparation of L-serine. Specifically, the invention provides a genetically engineered bacterium, and the sequence of a ribosome binding site of a glyA gene in the bacterium is shown as any one of SEQ ID NO: 53-58. The invention also provides a construction method of the genetically engineered bacterium for producing the L-serine or the L-serine derivative, and the ribosome binding site of the glyA gene of the bacterium is replaced by the ribosome binding site as shown in SEQ ID NO: 57 or 58.

Provided are a method for producing L-glutamic acid, and bacterium used therefor. L-glutamic acid is produced by culturing, in a culture medium, a Corynebacterium having L-glutamic acid-producing ability, the Corynebacterium being modified so as to retain a mutant glyA gene that codes for a mutant serine hydroxymethyltransferase and having a substitution of a glycine residue at position 265 in an amino acid sequence of a wild-type serine hydroxymethyltransferase to another amino acid residue, and collecting L-glutamic acid from the culture medium and / or a bacterial cell.

The invention relates to a tryptophan synthetase mutant and application of the tryptophan synthetase mutant in synthesis of an L-serine derivative, and belongs to the technical field of enzyme engineering. The tryptophan synthetase mutant provided by the invention takes an amino acid sequence as shown in SEQ ID NO.1 as a starting sequence, and is obtained by mutating 160th histidine into threonine, when L-tryptophan is produced, the enzyme activity is increased by 19.2% and the yield is increased by 16.25% compared with that of a wild type, and when L-cysteine is produced, the enzyme activity is increased by 17.62% and the yield is increased by 19.39% compared with that of the wild type. Serine hydroxymethyltransferase is introduced into an expression system, a reaction system with glycine as a substrate is constructed, the yield of the mutant H160T during production of L-tryptophan is increased by 19.86% compared with that of a wild type enzyme, the yield of the mutant H160T during production of L-cysteine is increased by 16.67% compared with that of the wild type enzyme, multiple purposes of one enzyme and multiple purposes of one bacterium are achieved, and the yield of the mutant H160T during production of L-tryptophan is increased by 19.86% compared with that of the wild type enzyme. A new thought and a new direction are provided for industrial production of the L-serine derivative.

The present invention provides isolated mammalian cells containing reduced or ablated expression of serine hydroxymethyltransferase 2 (SHMT2), as well as methods for preparing such cells and for using such cells in the production of recombinant proteins.

The present invention provides a recombinant genetically engineered bacterium for producing phytosphingosine, and its preparation method and use, belonging to the field of genetic recombination fermentation technology. The recombinant genetically engineered bacterium of the present invention is obtained by overexpressing the serine palmitoyltransferase LCB1 gene, LCB2 gene, tsc3 gene, 3-dehydrodihydrosphingosine reductase tsc10 gene, sphingosine hydroxylase sur2 gene, serine integrin tms1 gene, phosphoglycerate dehydrogenase ser3 gene in the genome of Saccharomyces cerevisiae, and knocking out the sphingosine kinase phospho-LCB4 gene, ceramide synthase LAG1 gene and LAC1 gene, LDB16 gene, sphingolipid homeostasis protein orm1 gene and orm2 gene, L-serine deaminase CHA1 gene, L-serine hydroxymethyltransferase SHM1 gene and SHM2 gene, and fatty acid elongase elo2 gene. The method for producing phytosphingosine using the recombinant genetically engineered bacterium is cost-effective, simple and efficient, with high phytosphingosine yield, and suitable for practical promotion and application.

The present disclosure provides an isolated mammalian cell comprising a reduced or eliminated expression of Serine Hydroxymethyltransferase 2 (SHMT2). Further provided are methods for preparing such cells and methods for using such cells for the production of recombinant proteins.

Provided are a hydroxymethyltransferase and a use of a cofactor or metabolic substrate thereof in preparation of drugs for treating neurodegenerative diseases. Specifically, a hydroxymethyl transfer reaction is performed on glycine residues in protein aggregates such as Poly-GA, Poly-GR, and TDP-43 by means of serine hydroxymethyltransferase 1 (SHMT1) and serine hydroxymethyltransferase 2 (SHMT2), so that the aggregates are degraded, thereby reducing pathological aggregation, and thus ameliorating the pathological condition of patients with neurodegenerative diseases such as ALS and FTD and delaying disease progression. A cofactor and a metabolic substrate of the hydroxymethyltransferase can promote the activity of the hydroxymethyltransferase, thereby enhancing the hydroxymethyl transfer effect on the aggregates such as Poly-GA, Poly-GR and TDP-43, and thus can also be used for treatment of the neurodegenerative diseases such as ALS and FTD.

The present invention discloses a mutant of serine hydroxymethyltransferase and its application. The amino acid sequence of the serine hydroxymethyltransferase is as shown in SEQ ID NO:1 in the sequence listing; the mutation occurs at one or more of the 19th, 310th, 138th, 168th, 363rd and 194th positions; wherein, the mutations corresponding to each position are M19K, S310K, K138R, K168R, F363R and G194A respectively. By site-directed mutagenesis of serine hydroxymethyltransferase derived from Pseudomonas aeruginosa strain 3Re2-7, the mutant improves the thermal stability of serine hydroxymethyltransferase and the catalytic activity of producing L-serine.

The present invention relates to a serine hydroxymethyltransferase mutant and a method for biosynthesizing L-glycine. In the present invention, serine hydroxymethyltransferase glyA is overexpressed in a host bacterium, and whole-cell catalysis is used to produce L-glycine; through site-directed mutagenesis, the catalytic direction of the enzyme is changed to make the catalysis favorable for the production of L-glycine; the mutant enzyme glyA A292V‑D392N The specific enzyme activity for catalyzing the production of L-glycine is increased to 1.52 U / mg, which is 204% higher than that of the original enzyme; the mutant enzyme glyA A292V‑D392N The conversion rate of whole-cell conversion for producing L-glycine can reach 61.8%, which is 2.8 times higher than that of the original enzyme glyA; after coupling serine hydroxymethyltransferase with the tetrahydrofolate cycle in the whole-cell catalysis system, only 5 mM to 10 mM of tetrahydrofolate is added, and the yield of L-glycine is 14.03 g / L at 12 h, and the substrate conversion rate is increased to 93.2%, effectively reducing the addition amount of the substrate tetrahydrofolate, reducing the catalytic cost, and greatly improving the production efficiency of L-glycine. The present invention is of great significance for the biosynthesis of L-glycine by biological methods.