A mutant tyrosine repressor that does not require tyrosine to induce expression of tyrosine phenol-lyase gene is obtained by introducing a mutation into a tyrosine repressor. A microorganism which is able to express large amounts of tyrosine phenol-lyase is obtained by introducing the mutant tyrosine repressor into the microorganism. The microorganism is useful for producing L-DOPA.
展开▼