MUTANT METHYLGLYOXAL SYNTHASE (MGS) FOR THE PRODUCTION OF A BIOCHEMICAL BY FERMENTATION

摘要

The present invention concerns a method for the production of a biochemical selected among lactic acid, acetol and 1,2-propanediol, comprising culturing a microorganism modified for an improved production of the biochemical selected among lactic acid, acetol and 1,2-propanediol in an appropriate culture medium and recovery of the desired biochemical which may be further purified wherein the microorganism expresses a methylglyoxal synthase (MGS) enzyme which activity is not inhibited by orthophosphate. The present invention concerns a mutant methylglyoxal synthase (MGS) comprising at least one amino acid residue in the protein sequence of the parent enzyme replaced by a different amino acid residue at the same position wherein the mutant enzyme has retained more than 50% of the methylglyoxal synthase activity of the parent enzyme and the methylglyoxal synthase activity of the mutant MGS is not inhibited by orthophosphate as compared to the parent enzyme.