title: Alcohol dehydrogenases that catalyse methyl formate synthesis participate in formaldehyde detoxification in the methylotrophic yeast Candida boidinii.
abstract: Methyl formate synthesis during growth on methanol by methylotrophic yeasts has been considered to play a role in formaldehyde detoxification. An enzyme that catalyses methyl formate synthesis was purified from methylotrophic yeasts, and was suggested to belong to a family of alcohol dehydrogenases (ADHs). In this study we report the gene cloning and gene disruption analysis of three ADH-encoding genes in the methylotrophic yeast Candida boidinii (CbADH1, CbADH2 and CbADH3) in order to clarify the physiological role of methyl formate synthesis. From the primary structures of these three genes, CbAdh1 was shown to be cytosolic and CbAdh2 and CbAdh3 were mitochondrial enzymes. Gene products of CbADH1, CbADH2 and CbADH3 expressed in Escherichia coli showed both ADH- and methyl formate-synthesizing activities. The results of gene-disruption analyses suggested that methyl formate synthesis was mainly catalysed by a cytosolic ADH (CbAdh1), and this enzyme contributed to formaldehyde detoxification through glutathione-independent formaldehyde oxidation during growth on methanol by methylotrophic yeasts.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Yurimoto
authors.forename: Bumjun
authors.initials: B
authors.lastname: Lee
authors.forename: Fumi
authors.initials: F
authors.lastname: Yasuda
authors.forename: Yasuyoshi
authors.initials: Y
authors.lastname: Sakai
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kato
mesh_terms: D000426:Alcohol Dehydrogenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002175:Candida / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D017931:DNA Primers; D005557:Formaldehyde / Q000493:pharmacokinetics*; D005563:Formic Acid Esters / Q000378:metabolism*; D008658:Inactivation, Metabolic / Q000502:physiology*; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data
chemical_list: D017931:DNA Primers; D005563:Formic Acid Esters; D007527:Isoenzymes; D005557:Formaldehyde; C025468:methyl formate; D000426:Alcohol Dehydrogenase