Kondrashin A A, Murataliev M B, Berezov T T
Biokhimiia. 1981 Dec;46(12):2164-73.
The membrane vesicles (proteoliposomes) have been reconstituted from soya bean phospholipids and mitochondrial transhydrogenase (EC 1.6.1.1) by a self-assembly procedure. Palmitoyl-CoA and Mg2+ inhibit the rate of NAD+ reduction by NADPH in these proteoliposomes as well as in these submitochondrial particles. After solubilization of transhydrogenase from submitochondrial particles membranes the specific activity of the enzyme decrease and then again increases (more than 4.5 times) after its incorporation into the proteoliposomal membranes. An addition of potassium cholate to the proteoliposomal suspension further increases the rate of the direct transhydrogenase reaction (by 35--40%) due to the function of the oppositely oriented molecules of transhydrogenase. The Michaelis constants for NAD+ and NADPH for transhydrogenase proteoliposomes are 27 microM and 30 microM, respectively. These data are practically coincident with the results obtained for submitochondrial particles (21 and 33 microM, respectively). Thus, the incorporation of transhydrogenase into proteoliposomal membranes results in reconstitution of both electrogenic and the most essential kinetic properties of the enzyme.
膜囊泡（蛋白脂质体）已通过自组装程序由大豆磷脂和线粒体转氢酶（EC 1.6.1.1）重构而成。在这些蛋白脂质体以及这些亚线粒体颗粒中，棕榈酰辅酶A和Mg2+会抑制NADPH还原NAD+的速率。从亚线粒体颗粒膜中溶解转氢酶后，该酶的比活性降低，然后在其掺入蛋白脂质体膜后再次增加（超过4.5倍）。向蛋白脂质体悬浮液中添加胆酸钾会由于转氢酶分子反向排列的作用而进一步提高直接转氢酶反应的速率（提高35%-40%）。转氢酶蛋白脂质体对NAD+和NADPH的米氏常数分别为27 microM和30 microM。这些数据与亚线粒体颗粒得到的结果（分别为21 microM和33 microM）几乎一致。因此，将转氢酶掺入蛋白脂质体膜会导致该酶的电生性和最基本的动力学特性的重构。
