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：1980
卷号：77
期号：11
页码：6391-6395
DOI：10.1073/pnas.77.11.6391
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Cytochrome oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1 ) couples the aerobic oxidation of ferrocytochrome c to the cyclical transport of monovalent cations or to the active transport of monovalent and divalent cations. This transport capability is mediated by an intracomplex ion-transport chain of two protein-bound molecules of cardiolipin per molecule of cytochrome oxidase. Cardiolipin in a two-phase system shows the identical ionophoric pattern as does the cytochrome oxidase coupled system. A molecular model of the cardiolipin chain suggests the possibility of a cage-like structure through which cations can be transferred from phosphate group to phosphate group. The ion-transport chain and the electron-transport chain are anchored to the same set of subunits (I+IV); the close proximity of the two chains argues for the direct coupling of electron and cation flow. The ion-transport chain of cytochrome oxidase provides an introduction to the molecular mechanisms by which ions are moved across membranes in energy-coupling systems.
