title: Class III alcohol dehydrogenase from Saccharomyces cerevisiae: structural and enzymatic features differ toward the human/mammalian forms in a manner consistent with functional needs in formaldehyde detoxication.
abstract: Alcohol dehydrogenase class III (glutathione-dependent formaldehyde dehydrogenase) from Saccharomyces cerevisiae was purified and analyzed structurally and enzymatically. The corresponding gene was also analyzed after cloning from a yeast genome library by screening with a probe prepared through PCR amplification. As with class III alcohol dehydrogenase from other sources, the yeast protein was obtained in two active forms, deduced to reflect different adducts/modifications. Protein analysis established N-terminal and C-terminal positions, showing different and specific patterns in protein start positions between the human/mammalian, yeast, and prokaryotic forms. Km values with formaldehyde differ consistently, being about 10-fold higher in the yeast than the human/mammalian enzymes, but compensated for by similar changes in kcat values. This is compatible with the different functional needs, emphasizing low formaldehyde concentration in the animal cells but efficient formaldehyde elimination in the microorganisms. This supports a general role of the enzyme in formaldehyde detoxication rather than in long-chain alcohol turnover.
authors.affiliation: Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Spain.
authors.forename: M R
authors.initials: MR
authors.lastname: Fernández
authors.forename: J A
authors.initials: JA
authors.lastname: Biosca
authors.forename: A
authors.initials: A
authors.lastname: Norin
authors.forename: H
authors.initials: H
authors.lastname: Jörnvall
authors.forename: X
authors.initials: X
authors.lastname: Parés
mesh_terms: D000426:Alcohol Dehydrogenase / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D000445:Aldehyde Oxidoreductases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002845:Chromatography; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D017931:DNA Primers; D004331:Drosophila melanogaster / Q000201:enzymology; D017886:Durapatite; D004926:Escherichia coli / Q000201:enzymology; D006736:Horses; D006801:Humans; D007700:Kinetics; D008322:Mammals; D051379:Mice; D008969:Molecular Sequence Data; D049831:Octopodiformes / Q000201:enzymology; D016133:Polymerase Chain Reaction; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid
chemical_list: D017931:DNA Primers; D011994:Recombinant Proteins; D017886:Durapatite; D000426:Alcohol Dehydrogenase; C020145:formaldehyde dehydrogenase (glutathione); D000445:Aldehyde Oxidoreductases