Polypeptide having D-lactate dehydrogenase activity, polynucleotide encoding the polypeptide, and process for production of D-lactic acid

摘要

Highly productive D-lactic acid fermentation uses a transformant obtained by introducing into a host cell a polynucleotide encoding a polypeptide according to any one of the following (A) to (C) in such a manner that the polypeptide is expressed, which polypeptide has a D-lactate dehydrogenase activity higher than those of conventional polypeptides: (A) a polypeptide having the amino acid sequence shown in SEQ ID NO:1 or 2; (B) a polypeptide having the same amino acid sequence as shown in SEQ ID NO:1 or 2 except that one or several amino acids are substituted, deleted, inserted and/or added, which polypeptide has a D-lactate dehydrogenase activity; and (C) a polypeptide having an amino acid sequence which has a sequence identity of not less than 80% to the amino acid sequence shown in SEQ ID NO:1 or 2, which polypeptide has a D-lactate dehydrogenase activity.

主权项

1. A vector comprising an isolated polynucleotide comprising any one of the following (a) to (g):
(a) a polynucleotide having the nucleotide sequence shown in SEQ ID NO:3 or 4; (b) a polynucleotide having the same nucleotide sequence as shown in SEQ ID NO:3 or 4 except that at least one and up to 40 nucleotides are substituted, deleted, inserted and/or added, which polynucleotide encodes a polypeptide having a D-lactate dehydrogenase (D-LDH) activity; (c) a polynucleotide which hybridizes under highly stringent conditions in the presence of 50% formamide at 65° C. with the polynucleotide having the nucleotide sequence shown in SEQ ID NO:3 or 4 or a full complementary strand thereof, which polynucleotide encodes a polypeptide having a D-LDH activity; (d) a polynucleotide having a nucleotide sequence which has a sequence identity of not less than 95% to the nucleotide sequence shown in SEQ ID NO:3 or 4, which polynucleotide encodes as polypeptide haying a D-lactate dehydrogenase activity; (e) a polynucleotide encoding as polypeptide having the amino acid sequence shown in SEQ ID NO: 1 or 2; (f) a polynucleotide encoding a polypeptide having an amino acid sequence which has a sequence identity of not less than 95% to the amino acid sequence shown in SEQ ID NO:1 or 2, which polypeptide has a D-lactate dehydrogenase activity; and (g) a polynucleotide encoding a polypeptide having the same amino acid sequence as shown in SEQ ID NO:1 or 2 except that at least one and up to 10 amino acids are substituted, deleted, inserted and/or added, which polypeptide has a D-lactate dehydrogenase activity.