A method for producing L-amino acid using a bacterium of the family Enterobacteriaceae in which the weakened gshA gene expression

摘要

1. A method for producing L-amino acid comprising: (i) growing bacteria producing L-amino acids Enterobacteriaceae family in a medium to produce and excrete said L-amino acid in culture broth, bacteria, or both; and (ii) collecting said L-amino acid from the culture broth, bacteria or both, characterized in that the said bacterium is modified so that gene expression gshA oslablena.2. A method according to claim. 1, characterized in that the said bacterium belongs to the genus Escherichia.3. A method according to claim. 2, characterized in that the said bacterium is Escherichia coli.4. A method according to claim. 1, characterized in that the said bacterium belongs to the genus Pantoea.5. A method according to claim. 4, wherein said bacterium is Pantoea ananatis.6. A method according to any one of claims 1-5, characterized in that said gshA gene expression is weakened due to inactivation gshA.7 gene. A method according to claim. 6, characterized in that said deletirovan.8 gshA gene. . A method according to claim 1, characterized in that said gene gshA selected from the group consisting of: (A) a DNA comprising the nucleotide sequence of SEQ ID NO: 1; (B) DNA comprising the variant nucleotide sequence SEQ ID NO: 1 due to degeneracy genetic code; (C) DNA having an identity of not less than 60% relative to the complete nucleotide sequence of SEQ ID nO: 1 and wherein said DNA encodes a protein having activity γglutamat-tsisteinligazy; (D) DNA encoding a protein comprising the amino acid sequence of SEQ ID NO: 2; and (E) DNA encoding a variant protein comprising the amino acid sequence of SEQ ID NO: 2, but which contains one or more mutations involving substitution, deletion, insertion or addition of one or several amino acid residues, and wherein said variant protein has