- 作者: Jan-Olov Hoog Jesper J. Hedberg Patrik Stromberg Stefan Svensson
- 作者服務機構: Department of Medical Biochemistry and Biophysics, Karolinska Instilutet, Stockholm, Sweden
- 中文摘要: --
- 英文摘要: Mammalian alcohol dehydrogenase (ADH) constitutes acomplex system with different forms and extensive mul-tiplicity (ADH1-ADH6) that catalyze the oxidation andreduction of a wide variety of alcohols and aldehydes.The ADH1 enzymes, the classical liver forms, are in-volved in several metabolic pathways beside the oxida-tion of ethanol, e.g. norepinephrine, dopamine, seroto-nin and bile acid metabolism. This class is also able tofurther oxidize aldehydes into the corresponding carbox-ylic acids, i.e. dismutation.ADH2, can be divided into twosubgroups, one group consisting of the human enzymetogether with a rabbit form and another consisting of therodent forms. The rodent enzymes almost lack ethanol-oxidizing capacity in contrast to the human form, indicat-ing that rodents are poor model systems for human etha-nol metabolism. ADH3 (identical to glutathione-depen-dent formaldehyde dehydrogenase) is clearly the ances-tral ADH form and S-hydroxymethylglutathione is themain physiological substrate, but the enzyme can stilloxidize ethanol at high concentrations. ADH4 is solelyextra hepatica lly expressed and is probably involved infirst pass metabolism of ethanol beside its role in retinolmetabolism. The higher classes, ADH5 and ADH6, havebeen poorly investigated and their substrate repertoire isunknown. The entire ADH system can be seen as a gen-eral detoxifying system for alcohols and aldehydes with-out generating toxic radicals in contrast to the cyto-chrome P450 system.
- 中文關鍵字: --
- 英文關鍵字: Alcohol dehydrogenase. Enzyme Kinetics. Protein expression