Nucleic acids encoding stable mutants of D-N--carbamoylase

摘要

The present invention relates to mutants of D-N-- carbamylase wherein at least one of the cysteines in position 243, 250 and 279 of the amino acid sequence of the wild type enzyme is substituted with a different residue selected from natural amino acids; a recombinant plasmid comprising a nucleotidic sequence which encodes for at least one of the mutants of D-N--carbamylase, host microorganisms transformed with said plasmid and a process for the preparation of these mutants by the culture of said microorganisms. The mutants of D-N-- carbamoylase have a higher enzymatic stability than that of the wild type enzyme and are particularly useful in the preparation of D--amino acids providing an improvement in the production yields.