克氏锥虫Mg2+激活的三磷酸腺苷酶的增溶作用及某些特性

Solubilization and some properties of the Mg2+-activated adenosine triphosphatase from Trypanosoma cruzi.

Frasch A C, Cazzulo J J, Stoppani A O

Instituto de Química Biológica, Facultad de Medicina, Universidad de Buenos Aires, Argentina.

Comp Biochem Physiol B. 1978;61(2):207-12. doi: 10.1016/0305-0491(78)90162-1.

Abstract

Grinding of epimastigotes of Trypanosoma cruzi with glass powder in a mortar yielded a Mg2+-activated adenosine triphosphatase (ATPase) preparation which was highly sensitive to oligomycin. 2. Chloroform treatment of the particles resulted in the solubilization of an ATPase which was (a) activated by MgCl2; (b) slightly inhibited by CaCl2; (c) activated by sulphite and bisulphite; (d) had an optimum pH of 7.6; and (e) had a Km for ATP of 2.1 mM (in the presence of 4 mM MgCl2). 3. The solubilized enzyme was insensitive to oligomycin and leucinostatin, which inhibited the membrane-bound ATPase, though inhibited by efrapeptin and quercetin. 4. The results indicate that the chloroform-extracted enzyme is a soluble F1-ATPase similar to those isolated from mammalian mitochondria.

摘要

将克氏锥虫的上鞭毛体与玻璃粉在研钵中研磨，得到一种对寡霉素高度敏感的Mg2+激活的三磷酸腺苷酶（ATP酶）制剂。2. 用氯仿处理这些颗粒，可使一种ATP酶溶解，该酶：（a）被MgCl2激活；（b）被CaCl2轻微抑制；（c）被亚硫酸盐和亚硫酸氢盐激活；（d）最适pH为7.6；（e）在存在4 mM MgCl2的情况下，对ATP的Km为2.1 mM。3. 溶解的酶对寡霉素和亮抑蛋白酶不敏感，这两种物质可抑制膜结合的ATP酶，但该酶被埃弗拉肽素和槲皮素抑制。4. 结果表明，氯仿提取的酶是一种可溶性F1-ATP酶，类似于从哺乳动物线粒体中分离出的那些酶。