Isolated nucleic acid molecules, designated MR nucleic acid molecules, which encode novel MR proteins from Corynebacterium glutamicum are described which are involved in biosynthesis of a fine chemical, e.g., methionine biosynthesis. The invention also provides antisense nucleic acid molecules, recombinant expression vectors containing MR nucleic acid molecules, and host cells into which the expression vectors have been introduced. The invention still further provides methods of producing methionine from microorganisms, e.g., C. glutamicum, which involve culturing recombinant microorganisms which overexpress or underexpress at least one MR molecule of the invention under conditions such that methionine is produced. Also featured are methods of producing a fine chemical, e.g., methionine, which involve culturing recombinant microorganisms having selected MR genes deleted or mutated under conditions such that the fine chemical, e.g., methionine, is produced.