title: The effect of pyruvate decarboxylase gene knockout in Saccharomyces cerevisiae on L-lactic acid production.
abstract: 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 Saccharomyces cerevisiae that has both pyruvate decarboxylase genes (PDC1 and PDC5) disrupted in the genetic background to express two copies of the bovine L-lactate dehydrogenase (LDH) 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 pdc1 pdc5 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.
authors.affiliation: Biotechnology Laboratory, Toyota Central R&D Labs Inc, Aichi, Japan. e1168@most.tytlabs.co.jp
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ishida
authors.forename: Satoshi
authors.initials: S
authors.lastname: Saitoh
authors.forename: Toru
authors.initials: T
authors.lastname: Onishi
authors.forename: Kenro
authors.initials: K
authors.lastname: Tokuhiro
authors.forename: Eiji
authors.initials: E
authors.lastname: Nagamori
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kitamoto
authors.forename: Haruo
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D001709:Biotechnology / Q000379:methods*; D005285:Fermentation; D005800:Genes, Fungal; D005818:Genetic Engineering; D019344:Lactic Acid / Q000096:biosynthesis*; D009154:Mutation; D011767:Pyruvate Decarboxylase / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D019344:Lactic Acid; C101504:PDC1 protein, S cerevisiae; D011767:Pyruvate Decarboxylase