嗜热细胞色素氧化酶在进行广泛的蛋白酶解后仍保留质子泵浦和氧化酶活性。

Proton pumping and oxidase activity of thermophilic cytochrome oxidase remain after its extensive proteolysis.

作者信息

Yanagita Y, Sone N, Kagawa Y

出版信息

Biochem Biophys Res Commun. 1983 Jun 15;113(2):575-80. doi: 10.1016/0006-291x(83)91764-3.

Abstract

A proton-pumping heme aa3-type cytochrome oxidase purified from the thermophilic bacterium PS3 was treated with trypsin, thermolysin, chymotrypsin, subtilisin, or pronase. The cleavage of the oxidase subunits and the effects of their cleavage on the oxidase activity and proton-pumping in reconstituted vesicles were studied. Trypsin and thermolysin cleaved some of the oxidase subunits without affecting the proton-pumping, but subtilisin and pronase cleaved all the subunits resulting in partial decrease in both activities. Chymotrypsin had an intermediate effect. Subunit II of this enzyme contains heme c which is also cleaved by proteases.

摘要

从嗜热细菌PS3中纯化得到的质子泵血红素aa3型细胞色素氧化酶，用胰蛋白酶、嗜热菌蛋白酶、胰凝乳蛋白酶、枯草杆菌蛋白酶或链霉蛋白酶进行处理。研究了氧化酶亚基的裂解及其裂解对重组囊泡中氧化酶活性和质子泵功能的影响。胰蛋白酶和嗜热菌蛋白酶裂解了一些氧化酶亚基，但不影响质子泵功能，而枯草杆菌蛋白酶和链霉蛋白酶裂解了所有亚基，导致两种活性部分降低。胰凝乳蛋白酶具有中间效应。该酶的亚基II含有血红素c，也会被蛋白酶裂解。