Ferencz-Biro K, Pietruszko R
Alcohol Clin Exp Res. 1984 May-Jun;8(3):302-7. doi: 10.1111/j.1530-0277.1984.tb05516.x.
Propiolaldehyde--a metabolite of pargyline (Shirota et al., 1979) can function as an inhibitor or as a substrate of human aldehyde dehydrogenase (EC 1.2.1.3), dependent on conditions. In the presence of high concentration of NAD, propiolaldehyde is a substrate for both the cytoplasmic E1 isozyme and the mitochondrial E2 isozyme. The Km values are comparable to those with other short chain aldehydes; the maximal velocity is also similar for E2 but lower by about three-fold for E1. Preincubation with propiolaldehyde in the absence of NAD produces inactivation with K1 values of 1.6 microM for E1 and 1.8 microM for E2. NAD, but not propanal, protects both isozymes against inactivation with propiolaldehyde.
丙炔醛——帕吉林的一种代谢产物（Shirota等人，1979年），根据条件不同，它既可以作为人醛脱氢酶（EC 1.2.1.3）的抑制剂，也可以作为其底物。在高浓度烟酰胺腺嘌呤二核苷酸（NAD）存在的情况下，丙炔醛是细胞质E1同工酶和线粒体E2同工酶的底物。其米氏常数（Km值）与其他短链醛的Km值相当；E2的最大反应速度也相似，但E1的最大反应速度约低三倍。在没有NAD的情况下，用丙炔醛预孵育会导致失活，E1的失活常数（K1值）为1.6微摩尔，E2为1.8微摩尔。NAD而非丙醛可保护这两种同工酶不被丙炔醛失活。
