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：1982
卷号：79
期号：13
页码：3978-3982
DOI：10.1073/pnas.79.13.3978
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The cooperative equilibrium binding of Ca2+ by sarcoplasmic reticulum ATPase, as modulated by pH, is analyzed by statistical mechanical treatment of a theoretical model. The model consists of four equivalent subunits, in the form of a square, with nearest-neighbor interactions. Each subunit has one site for binding of one Ca2+ or one proton, but not both. Binding of either ligand on a subunit induces a conformational change in the subunit that alters its interaction with its two neighbors. The model gives good agreement with experimental binding data. It should prove useful as a starting point in the analysis of steady-state ATPase activity as a function of Ca2+ and H+ concentrations.
