D-Amino acid production by E.coli co-expressed three genes encoding hydantoin racemase,D-hydantoinase and N-carbamoyl-D-amino acid amidohydrolase

摘要

Three genes respectively encoding D-specific hydantoinase (DHHase),N-carbamoyl-D-amino acid amidohydrolase (DCHase) and hydantoin racemase (HRase) were co-expressed in E.coli in a system designed for the efficient enzymatic production of D-amino acids via a combination of hydantoin hydrolysis and hydantoin racemization.With the use of whole cells,the D-forms of eight amino acids-D-phenylalanine,D-tyrosine,D-tryptophan,O-benzyl-D-serine,D-valine,D-norvaline,D-leucine and D-norleucine-were efficiently converted from the corresponding DL-5-monosubtituted hydantoin compounds.