75 results about "Corynebacterium efficiens" patented technology

L-Arginine is produced by culturing a coryneform bacterium in which an arginine repressor involved in L-arginine biosynthesis is deleted by disrupting a gene coding for the repressor, and which has L-arginine producing ability in a medium to produce and accumulate L-arginine in the medium, and collecting the L-arginine from the medium.

A colibacillus-corynebacterium inducible expression carrier pDXW-8 and a building method thereof belong to the technical field of genetic engineering. The inducible expression carrier pDXW-8 can be copied and stably exists in colibacillus and corynebacterium and comprises a tac promoter, a terminator rrnBT1T2, a resistance marker card kanamycin mark resistance gene, a negative regulation gene laclPE104 and a multi-cloning site, wherein the tac promoter plays a transcript promoting function in the colibacillus and the corynebacterium, the terminator rrnBT1T2 has a transcript stopping function, the resistance marker card kanamycin mark resistance gene is used for selecting transformants of the corynebacterium, the negative regulation gene is used for severely controlling expression of the tac promoter, and the multi-cloning site includes 11 signal limited incision enzyme sites. In the corynebacterium, the carrier is moderate in foreign protein expression, and is particularly adaptable to study on corynebacterium metabolic engineering.

The invention discloses a construction method and an application of a corynebacterium gene continuous knockout system, belonging to the technical field of genetic engineering. The corynebacterium gene continuous knockout system comprises a template plasmid and a temperature-sensitive expression plasmid, wherein the template plasmid provides a kan fragment (also known as a kan box) with loxp or variant loxL/R sites at two ends; and the temperature-sensitive expression plasmid carries a Cm resistance gene cat and a temperature-sensitive C. glutamicum replicon, expresses a Cre recombinant enzyme and is used for removing a Km resistance gene kan. The corynebacterium continuous knockout system disclosed by the invention can be generally used for continuous gene transformation of corynebacterium and has the advantages of simplicity and convenience in operation and high efficiency. By utilizing the knockout system, gene (continuous) knockout of three major typical subspecies genomes of the corynebacterium can be successfully completed, and the system is proved to be applicable to research and production of corynebacterium metabolites.

The invention relates to the field of microbial technology, in particular to a recombinant strain, a method for preparing the recombinant strain and a method for producing L-valine from the recombinant strain. According to the recombinant strain, corynebacterium serves as a starting strain for transformation, and the transformation process includes the steps of conducting point mutation on the ilvN gene and knocking out the avtA gene. The recombinant strain is obtained by conducting point mutation on the ilvN in a valine metabolism path and knocking out the avtA gene for transaminase coding; through fermentation culture, the yield of L-valine can reach 12.2 g/L, and generation of the by-product alanine is greatly reduced.

The invention provides a recombinant bacterial strain for high-yield production of L-lysine, and a construction method and application of the recombinant bacterial strain. A polynucleotide sequence comprises a modified pobB gene coding polynucleotide sequence as shown in SEQ ID NO:2, and the invention provides a recombinant protein coded by the polynucleotide sequence, the recombinant bacterial strain containing the polynucleotide sequence, a construction method of the recombinant bacterial strain, and an application of the recombinant bacterial strain in fermentation production of L-lysine. According to the recombinant strain disclosed by the invention, point mutation is carried out on the nucleotide sequence of an open reading frame coding region of the pobB gene in wild-type corynebacterium glutamicum to obtain the recombinant strain modified by the coding region of the pobB gene, and the yield of L-lysine is realized compared with the yield of L-lysine by using wild bacterial strains.

The invention relates to a corynebacterium glutamicum establishment method for increasing the yield of L-lysine and improving the stability of the L-lysine. According to the method, after a Tnp7a geneof corynebacterium glutamicum is inactivated, the corynebacterium glutamicum is established, and an amino acid sequence of the Tnp7a gene is shown in SEQ ID NO:1. According to the corynebacterium glutamicum establishment method for increasing the yield of the L-lysine and improving the stability of the L-lysine, the endogenous gene Tnp7a of the established corynebacterium glutamicum is inactivated, the transposition effect, caused when an insertion sequence is activated due to an environment change, of the corynebacterium glutamicum in the preservation and fermentation process is lowered, thestrain degeneration progress, caused by mutation or frame shift generated by transposition or adjustment on expression of adjacent genes through promoters carried by a genome, of the genome is blocked, and the yield of the L-lysine is increased.

A coryneform bacterium transformant prepared by transferring an exogenous gene which encodes a protein having a sugar transporter function into a coryneform bacterium capable of utilizing D-xylose.

The invention discloses a corynebacterium glutamicum engineering bacterium for anaerobic conversion to produce succinic acid, and a building method and application thereof, and belongs to the field of genetic engineering. A pyruvate carboxylase gene of the corynebacterium glutamicum and phosphoenolpyruvate carboxylase from escherichia coli are cloned to corynebacterium glutamicum (ATCC13032); a lactate dehydrogenase gene of the corynebacterium glutamicum is knocked out in a homologous recombination manner. By adopting the lactic dehydrogenase-defective corynebacterium glutamicum for coexpression of a carboxylase gene, anaerobic production of succinic acid is carried out in a cell reutilization manner, so that the yield of succinic acid can be greatly improved; the yield can be up to 75g/L; the conversion rate of saccharic acid is 75%; the corynebacterium glutamicum engineering bacterium has a good application prospect; a fermentation model, especially a fermentation model for cell reutilization is built according to the optimum condition for biological transformation of succinic acid; the acid-production performance in repeated batch transformation process of cells can be basically kept stable.

The invention provides an engineering bacterium for producing caffeine by fermentation. The engineering bacterium is a recombinant corynebacterium glutamicum which is established by guiding a key enzyme gene in a caffeine biosynthetic pathway into a corynebacterium glutamicum. The key enzyme gene in the caffeine biosynthetic pathway is over-expressed, so that the corynebacterium glutamicum is capable of producing the caffeine; and moreover, a large number of caffeine as products can be secreted out of cells, separation and purification steps are few, yield of the caffeine is high, and a flask fermentation result shows that the yield of the caffeine reaches 3.75 mg/L, so that the recombinant engineering bacterium has a good industrial application prospect, and lays a theoretical foundation for producing food safety-level caffeine by fermentation by using the corynebacterium glutamicum.

L-Arginine or L-lysine is produced by culturing a coryneform bacterium having an L-arginine- or L-lysine-producing ability and modified so that glutamine synthetase activity is enhanced, e.g., a coryneform bacterium which is modified so that activity regulation of glutamine synthetase by adenylylation is eliminated, in a medium to produce and accumulate L-arginine or L-lysine in the medium and collecting the L-arginine or L-lysine from the medium.

The invention discloses a recombined Corynebacterium glutamicum for producing L-Phe and a constructing method and the application thereof, and belongs to the field of metabolic engineering. In Corynebacterium glutamicum ATCC 13032, two shuttle expression vectors pEC-XK99E and pXMJ19 of the Corynebacterium glutamicum and escherichia coli are used for expressing eight key enzyme genes comprising aroF<fbr>, tktA, ppsA, aroL, pheA<fbr>, aroE, aroA and tyrB in a L-Phe synthetic route, two promoters Ptac and Plac of different intensities are used for carrying out combinational expression on the eight genes to improve the L-Phe yield, the L-Phe yield can reach as high as 5.59+/-0.11 g/l, and accumulated shikimic acid is 0.31+/-0.11 g/L. According to the method, over expression is achieved for the L-Phe shikimic acid key enzyme genes, and the yield of L-Phe produced by the Corynebacterium glutamicum in a fermentation mode is improved.

The present invention relates to a strain producing L-tryptophan and use thereof in fermentation. Specifically, the L-tryptophan producing capability of the strain is greatly improved through attenuating or blocking an oxidation stage of a pentose phosphate pathway of engineering bacteria (such as Escherichia coli or Corynebacterium glutamicum) with a genetic engineering method.

The present invention discloses a corynebacterium glutamate for synthesizing geraniol and a construction method and application of corynebacterium glutamate. The construction method of corynebacteriumglutamate comprises the following steps: connecting a saccharomyces cerevisiae-derived mutant geranyl pyrophosphate synthase gene ERG20<F96W-N127W> and a valerian-derived geranol synthase gene tVoGEStruncated through cutting off of C-terminal 53 amino acid residues by fusion PCR, adding a ribosome binding site sequence to a homologous region, inserting SacI and XbaI enzyme cutting sites of a corynebacterium glutamate expression plasmid pEC-XK99E to obtain a plasmid 1; converting the plasmid 1 into corynebacterium glutamate to obtain corynebacterium glutamate 1 for synthesizing geraniol. Theconstruction method provides more precursors and short fermentation time (42 to 48 hours) for the synthesis of geraniol, and corresponding by-products are not detected out by GC-MS detection.

The invention discloses a corynebacterium promoter detection vector and a construction method and application thereof, and belongs to the technical field of genetic engineering. The corynebacterium promoter detection vector pDXW-11 can be used for screening promoters which can be efficiently expressed in corynebacteria; by detecting plasmids, a strong corynebacterium promoter tac-M which can be efficiently expressed in the corynebacteria is screened; and the corynebacterium promoter detection vector is particularly suitable for the research and production of metabolites of the corynebacteria.

A method for producing L-glutamic acid by culturing a coryneform bacterium which has L-glutamic acid producing ability and which has been modified so that expression of the fasR gene is enhanced in a medium to produce and accumulate L-glutamic acid in the medium or cells, and collecting L-glutamic acid from the medium or cells.

The invention relates to a construction method of corynebacterium glutamicum engineering bacteria for high production of L-lysine. According to the method, the engineering bacteria are constructed by inactivating an NCgl1221 gene of corynebacterium glutamicum, wherein the nucleotide sequence of an NCgl1221 gene encoding frame is shown as SEQ ID NO. 1. The invention provides a construction method of a corynebacterium glutamicum strain for high production of the L-lysine; the constructed strain can obviously decrease glutamicum exocytosis due to the inactivation of the endogenous gene NCgl1221; compared with a wild strain, the strain can be used for producing high-concentration L-lysine and can effectively reduce the content of glutamicum which is a byproduct of a fermentation liquor; and the strain, as an L-lysine production strain, can further reduce production cost and purification cost.

The invention discloses recombinant corynebacterium glutamicum in high L-lysine yield and a construction method thereof, and belongs to the technical field of genetic engineering. According to the recombinant corynebacterium glutamicum disclosed by the invention, a phosphoglyceraldehyde dehydrogenase encoding gene gapC derived from Clostridium acetobutylicum ATCC824 is heterogeneously expressed bytaking corynebacterium glutamicum CICC 23604 as an original strain and adopting CRISPR-Cas9 gene editing technology, and supply of intracellular NADPH (Nicotinamide Adenine Dinucleotide Phosphate) isincreased; a homoserine kinase encoding gene thrB is knocked out, accumulation of a byproduct-threonine during a fermentation process is reduced, corynebacterium glutamicum genetically engineered bacteria with the accumulation of L-lysine can be obtained, the yield is up to 42g/L, and foundation is laid for producing the L-lysine through further metabolism engineering reform of the corynebacterium glutamicum.

The invention provides a temperature-sensitive recombinant corynebacterium glutamicum producing glutamic acid. The temperature-sensitive recombinant corynebacterium glutamicum is obtained by transforming wild type corynebacterium glutamicum ( C. glutamicum ATCC 13032) and knocking out two key genes in a genome of the corynebacterium glutamicum in a peptidoglycan synthesis route, namely UDP-N-enol form acetyl glucosamine transferase gene (murA) and UDP-N-acetyl cell wall acidohydrogenase gene (murB), the glutamic acid yield of the recombinant corynebacterium glutamicum is improved obviously, and the glutamic acid yield is 4-7 g/L under the condition that the fermentation temperature rises to 38.5 DEG C.

The invention discloses a multiplex quantitative PCR (Polymerase Chain Reaction) primer, a probe, a kit and a detection method for corynebacterium bacteria and Klebsiella corynebacterium. Aiming at corynebacterium bacterium 23S rRNA genes and Klebsiella corynebacterium 16S rRNA gene sequences, specific primers and probes are designed, whether the corynebacterium bacteria and Klebsiella corynebacterium exist in a biological sample can be identified by utilizing multiplex quantitative PCR. The primers and probes have an important guiding role in clinical targeted selective use of antibiotics. Due to reasonable usage of the antibiotics, the course of granulomatous mastitis can be effectively shortened, the condition that breast tissues are removed during the operation is avoided, physical and psychological trauma of a patient can be greatly alleviated, and an etiological basis is provided for clinical diagnosis and treatment of the granulomatous mastitis.

Provided are an Escherichia species microorganism and Corynebacterium species microorganism that are transformed with a foreign NADP dependent glyceraldehydes-3-phosphate dehydrogenase gene and have the ability to produce L-lysine and a method of producing L-lysine using the microorganisms.

The present invention relates to a Corynebacterium sp. strain having an activity of NADP-dependent glyceraldehyde-3-phosphate dehydrogenase and an improved productivity of L-lysine, and a method for producing L-lysine using the same. According to the Corynebacterium sp. strain of the present invention and the method for producing L-lysine using the same, L-lysine can be produced in a high yield.

A host cell includes a heterogeneous expression unit including: (a) a polynucleotide encoding a mevalonate kinase derived from a microorganism belonging to a genus selected from Methanocella, Corynebacterium, Methanosaeta, and Nitrosopumilus, and (b) a promoter operatively linked to the polynucleotide. The host cell is used to produce mevalonate kinase, mevalonate-5-phosphate, and isoprenoid compounds.

The invention discloses a glutamate decarboxylase gene and use thereof and belongs to the technical field of genetic engineering. In the invention, a glutamate decarboxylase gene gadB2 derived from Lactobacillus brevis, and a transportprotein gene gadC and a regulatory protein gene gadR, which are connected with the gadB2, are transferred into Corynebacterium glutamicum ATCC13032 through a corynebacterium expression vector pDXW8, and the recombinant Corynebacterium glutamicum can directly convert self accumulated glutamic acid into gamma-aminobutyric acid.