Bosron W F, Li T K
Enzyme. 1987;37(1-2):19-28. doi: 10.1159/000469238.
Human liver alcohol dehydrogenase (ADH) exists in multiple molecular forms which arise from the association of eight different types of subunits, alpha, beta 1, beta 2, beta 3, gamma 1, gamma 2, pi, and chi, into active dimeric molecules. A genetic model accounts for this multiplicity as products of five gene loci, ADH1 through ADH5. Polymorphism occurs at two loci, ADH2 and ADH3, which encode the beta and gamma subunits. All of the known homodimeric and heterodimeric isoenzymes have been isolated and purified to homogeneity. Analysis of the steady-state kinetic properties and substrate and inhibitor specificities has shown substantial differences in the catalytic properties of the isoenzymes. For example, the Km values for NAD+ and ethanol vary as much as 1,000-fold among the isoenzymes. Some of the differences in catalytic properties can be related to specific amino acid substitutions in the ADH isoenzymes.
人类肝脏乙醇脱氢酶（ADH）以多种分子形式存在，这些形式源于八种不同类型的亚基（α、β1、β2、β3、γ1、γ2、π和χ）缔合形成活性二聚体分子。一种遗传模型将这种多样性解释为五个基因位点（ADH1至ADH5）的产物。多态性出现在两个位点，即ADH2和ADH3，它们分别编码β和γ亚基。所有已知的同二聚体和异二聚体同工酶都已被分离并纯化至同质状态。对稳态动力学性质以及底物和抑制剂特异性的分析表明，同工酶的催化性质存在显著差异。例如，同工酶之间NAD+和乙醇的Km值相差多达1000倍。催化性质的一些差异可能与ADH同工酶中的特定氨基酸取代有关。
