胆碱脱氢酶的动力学性质

本文对增溶胆碱脱氢酶的稳态初速度及产物抑制动力学做了。底物胆碱和ＰＭＳ的相互影响：变化一个底物的浓度，另一个底物的Ｋｍ及Ｖｍａｘ均变化。该酶的产物三甲胺 地 制表现为对底物胆碱非竞争性而地ＰＭＳ竞争性，在胆碱饱和的情况下，三甲胺乙醛对酶的抑制仍表现为对ＰＭＳ竞争性。这些结果表明增溶胆碱脱氢酶的催化机制搂双底物双产物乒乓机制。１－ＰＣ与９－ＡＣ对增溶胆碱脱氢酶均有抑制作用，且均为混和型抑制，Ｋ１分别

Kinetic Properties of Choline Dehydrogenase

The kinetic behavior of purified CDH had been investigated by steady state initial velocity studies and inhibition studies with products. Variations in the concentration of one substrate led to changes in the K m and V max for the other substrate. The product betaine aldehyde was a noncompetitive inhibitor with respect to choline, whereas it competed with PMS. The results were consistent with a Bi Bi Ping Pong mechanism. 1 PC (1 pyrenebutyrylcholine bromide) and 9 AC (9 anthrolcholine bromide) behaved as mixed inhibitors, with K i values of 0.3 mM and 3.67 mM respectively.