The Effect of Pyruvate Decarboxylase Gene Knockout in Saccharomyces cerevisiae on L-Lactic Acid Production
A plant- and crop-based renewable plastic, poly-lactic acid (PLA), is receiving attention as a new material for a sustainable society in place of petroleum-based plastics. We constructed a metabolically engineered <I>Saccharomyces cerevisiae</I> that has both pyruvate decarboxylase genes (<I>PDC1</I> and <I>PDC5</I>) disrupted in the genetic background to express two copies of the bovine <small>L</small>-lactate dehydrogenase (<I>LDH</I>) gene. With this recombinant, the yield of lactate was 82.3 g/liter, up to 81.5% of the glucose being transformed into lactic acid on neutralizing cultivation, although <I>pdc1</I> <I>pdc5</I> double disruption led to ineffective decreases in cell growth and fermentation speed. This strain showed lactate productivity improvement as much as 1.5 times higher than the previous strain. This production yield is the highest value for a lactic acid-producing yeast yet reported.
- Bioscience, biotechnology, and biochemistry
Bioscience, biotechnology, and biochemistry 70(5), 1148-1153, 2006-05-23
Japan Society for Bioscience, Biotechnology, and Agrochemistry