Patent ID: 8039238

Claim:
A bacterial or yeast transformant into which has been incorporated a lactate dehydrogenase gene coding sequence, wherein the lactate dehydrogenase coding sequence encodes a foreign protein having lactate dehydrogenase activity and pyruvic acid substrate affinity that equals or exceeds the pyruvic acid substrate affinity of the pyruvate decarboxylase inherent in the host organism, wherein a single copy of the lactate dehydrogenase gene coding sequence has been incorporated such that it is under the control of a genomic pyruvate decarboxylase gene promoter on the host chromosome, or such that it is under the control of a structural and functional homologue of the genomic pyruvate decarboxylase gene promoter, which replaces the genomic pyruvate decarboxylase gene promoter on the host chromosome, and wherein the pyruvate decarboxylase gene on the host chromosome is replaced with the single copy of the lactate dehydrogenase gene coding sequence, wherein the foreign protein is coded by the DNA sequence shown in SEQ ID NO:3.