期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1972
卷号：69
期号：10
页码：3004-3008
DOI：10.1073/pnas.69.10.3004
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The sulfenic acid form of glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12 ), which is an acyl phosphatase, will catalyze an acetyl phosphate-Pi exchange reaction. This exchange reaction is reversibly inhibited by the uncouplers of oxidative phosphorylation, 2,4-dinitrophenol, m-Cl carbonylcyanide-phenylhydrazone, pentachlorophenol, and 5-chloro-3-tert-butyl-2'-chloro-4'-nitrosalicylanalide, and is irreversibly inhibited by cyanide and dicumarol. An ATP-Pi exchange reaction similar to that catalyzed by mitochondria can be simulated by a system composed of oxidized glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase (EC 2.7.1.28 ), 3-phosphoglycerate, ATP, 32Pi, and appropriate cofactors. The ATP-Pi exchange is inhibited by uncouplers of oxidative phosphorylation. Higher concentrations of uncouplers will also inhibit the ATPase reaction catalyzed by the coupled enzyme system. The exchange reactions catalyzed by the sulfenic acid form of glyceraldehyde-3-phosphate are consistent with a sulfenyl carboxylate intermediate. On the basis of these observations, a reaction scheme has been postulated for covalent coupling in oxidative phosphorylation that includes a sulfenyl carboxylate as a nonphosphorylated, high energy intermediate and an acyl phosphate as a phosphorylated, high energy intermediate.
关键词：acyl-phosphatase ; sulfenyl carboxylate ; high-energy intermediate ; energy conservation
