Do H+ ions obscure electrogenic Na+ and K+ binding in the E1 state of the Na,K-ATPase?
نویسندگان
چکیده
In contrast to other P-type ATPases, the Na,K-ATPase binding and release of ions on the cytoplasmic side, to the state called E1, is not electrogenic with the exception of the third Na+. Since the high-resolution structure of the closely related SR Ca-ATPase in state E1 revealed the ion-binding sites deep inside the transmembrane part of the protein, the missing electrogenicity in state E1 can be explained by an obscuring counter-movement of H+ ions. Evidence for such a mechanism is presented by analysis of pH effects on Na+ and K+ binding and by electrogenic H+ movements in the E1 conformation of the Na,K-ATPase.
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ورودعنوان ژورنال:
- FEBS letters
دوره 532 1-2 شماره
صفحات -
تاریخ انتشار 2002