# US 8,465,952 B2 · Microorganism producing L-methionine precursor and the method of producing L-methionine precursor using the microorganism > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,465,952 B2 - Document ID: US8465952B2 - Status: Granted - Kind: B2 - Application number: 12/983,788 - Filed: 2011-01-03 - Published: 2011-08-25 - Granted: 2013-06-18 - Earliest claimed: 2008-04-04 - Assignees: Cj Cheiljedang Corporation - Applicants: Chul Ha Kim; So Young Kim; Young Uk Shin; Hye Won Um; Jin Sook Chang; Young Wook Cho; Han Jin Lee; In Kyung Heo; Chang II Seo; Kwang Ho Na - Inventors: Chul Ha Kim; So Young Kim; Young Uk Shin; Hye Won Um; Jin Sook Chang; Young Wook Cho; Han Jin Lee; In Kyung Heo; Chang II Seo; Kwang Ho Na - Web page: https://patentgrep.com/patent/US8465952B2 ## CPC - C12N 1/20: Bacteria; Culture media therefor - C12N 1/205: Bacterial isolates - C12N 9/0006: {acting on CH-OH groups as donors (1.1)} - C12N 9/1029: {transferring groups other than amino-acyl groups (2.3.1)} - C12N 9/1217: {Phosphotransferases with a carboxyl group as acceptor (2.7.2)} - C12P 13/06: Alanine; Leucine; Isoleucine; Serine; Homoserine - C12P 13/12: Methionine; Cysteine; Cystine - C12R 2001/19: Escherichia coli - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - C12P: FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE {(brewing of beer C12C; producing vinegar C12J; producing specific peptides or proteins C07K; producing enzymes C12N9/00; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification C12N15/00; measuring or testing processes involving enzymes or microorganisms C12Q; measuring or testing processes involving nucleic acid amplification reactions C12Q1/6844; fermentation processes to form a food composition, A21 or A23; compounds in general, see the relevant compound class, e.g. C01, C07)} - C12R: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES C12C - C12Q, RELATING TO MICROORGANISMS ## Abstract The present invention relates to a microorganism producing L-methionine precursor, O-acetylhomoserine, and a method of producing L-methionine precursor using the microorganism. ## Claims ### Claim 1 A method for producing methionine, comprising, a) culturing a microorganism that produces and releases O-acetylhomoserine, wherein the microorganism is characterized by the following: i) a homoserine O-acetyltransferase activity (EC2.3.1.31) is introduced and enhanced by the integration of a gene from Deinococcus radiodurans that encodes homoserine O-acetyltransferase; and ii) an aspartokinase or homoserine dehydrogenase activity (EC2.7.2.4 or 1.1.1.3) is enhanced, but one or more of endogenous cystathionine gamma synthase, endogenous O-succinylhomoserine sulfhydrylase, and endogenous O-acetylhomoserine sulfhydrylase activities are reduced, inhibited or inactivated, b) producing methionine from the released O-acetylhomoserine. ### Claim 2 (depends on 1) The method of claim 1, wherein the homoserine O-acetyltransferase has the amino acid sequence of Unipro database No. Q9RVZ8 (SEQ ID NO:32). ### Claim 3 (depends on 1) The method of claim 1, wherein the aspartokinase or homoserine dehydrogenase peptide has a mutation at amino acid position 345. ### Claim 4 (depends on 1) The method of claim 1, wherein the aspartokinase or homoserine dehydrogenase has the amino acid sequence of SEQ ID NO:27. ### Claim 5 (depends on 1) The method of claim 1, wherein the microorganism is an Escherichia sp. ### Claim 6 (depends on 1) The method of claim 1, wherein the microorganism is an Escherichia coli. ### Claim 7 (depends on 1) The method of claim 1, wherein the microorganism is derived from L-threonine, L-isoleucine or L-lysine producing strain. ### Claim 8 (depends on 1) The method of claim 1, wherein the activity of homoserine kinase is reduced, inhibited, or inactivated, or the microorganism does not have an endogenous gene encoding homoserine kinase. ### Claim 9 (depends on 1) The method of claim 1, wherein a transcription regulator of methionine synthetic pathway is weakened or inactivated. ### Claim 10 (depends on 1) The method of claim 1, wherein the microorganism is derived from the threonine producing strain Escherichia coli MF001 free from methionine-dependency having Accession No. KCCM 10568. ### Claim 11 (depends on 1) The method of claim 1, wherein the microorganism is derived from the threonine producing strain Escherichia coli FTR2533 having Accession No. KCCM 10541. ### Claim 12 (depends on 1) The method of claim 1, wherein the microorganism is Escherichia coli CJM-X(pthrA(M)-CL) having Accession No. KCCM 10921P. ### Claim 13 (depends on 1) The method of claim 1, wherein the microorganism is Escherichia coli CJM2-X(pthrA(M)-CL) having Accession No. KCCM 10925P. ### Claim 14 (depends on 1) The method of claim 1, wherein a biosynthetic pathway of threonine is suppressed. ### Claim 15 (depends on 1) The method of claim 1, wherein expression of endogenous homoserine O-succinyltransferase encoded by metA gene, endogenous transcription regulator of methionine synthetic pathway encoded by metJ, endogenous homoserine kinase encoded by thrB gene, or a combination thereof, is suppressed. ### Claim 16 (depends on 1) The method of claim 1, wherein the expression of thrA gene that encodes the aspartokinase or homoserine dehydrogenase is enhanced.