PROBLEM TO BE SOLVED: To provide a new method for producing L-cysteine by clarifying an enzyme supporting cysteine desulfhydrase activity of a bacterial strain of genus Escherichia and its gene and using the gene for breeding of the L-cysteine-producing bacterial strain. SOLUTION: The MalY regulatory protein (MalY) gene of an Escherichia strain is modified to give a strain having L-cysteine productivity and lowered or eliminated cysteine desulfhydrase activity. The modified strain is cultured in a medium to form and accumulate L-cysteine in the medium and the L-cysteine is separated from the medium, thus L-cysteine is produced. COPYRIGHT: (C)2010,JPO&INPIT
