摘要 |
Disclosed are an expression cassette for a gene encoding lactate dehydrogenase, which is required for preventing decreases in lactic acid yield and lactic acid production speed in continuously culturing a yeast capable of producing lactic acid under filtration through a separation membrane so that a high optical purity, a high lactic acid yield and a high lactic acid production speed can be achieved at the same time, a yeast having the preceding cassette, and a method of producing lactic acid by culturing the preceding yeast. The expression cassette for lactate dehydrogenase as described above is an expression cassette for lactate dehydrogenase having a gene encoding lactate dehydrogenase which is ligated to the downstream of a promoter, wherein the above-described promoter is a promoter of a gene which shows, in continuously culturing a yeast capable of producing lactic acid under filtration through a separation membrane, a gene expression amount that is 5 times or more larger than the average of the relative expression amounts of all genes 50 hours or later after the start of the culture. |