USE OF DIMETHYL DISULFIDE FOR METHIONINE PRODUCTION IN MICROORGANISMS

摘要

The present invention features improved processes and organisms for the production of methionine. The invention demonstrates that a ?metF organism or a ?metE AmetH organism, for example, mutants of C. glutamicum or E. coli, can use a methyl capped sulfide source, e.g., dimethyl disulfide (DMDS), as a source of both sulfur and a methyl group, bypassing the need for MetH/Met? and MetF activity and the need to reduce sulfate, for the synthesis of methionine. Also described in this patent are data implicating MetY (also called MetZ) as an enzyme that incorporates a methyl capped sulfide source, e.g., DMDS, into methionine. A ?metF ?metB strain of C. glutamicum can use a methyl capped sulfide source, e.g., DMDS, as a source of both sulfide and a methyl group. Furthermore, methionine production by engineered prototrophic organisms that overproduce O-acetyl-homoserine was improved by the addition of a methyl capped sulfide source, e.g., DMDS.