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. 1986 Jul 1;237(1):207–215. doi: 10.1042/bj2370207

A model for the phosphorylation of the Ca2+ + Mg2+-activated ATPase by phosphate.

R J Froud, A G Lee
PMCID: PMC1146967  PMID: 2948489

Abstract

We have shown that changes in fluorescence intensity for the Ca2+ + Mg2+-activated ATPase of sarcoplasmic reticulum labelled with fluorescein isothiocyanate following the addition of Ca2+ can give the ratio of the two conformations (E1 and E2) of the ATPase. We show that the fluorescence response to Ca2+ is unaffected by Mg2+, phosphate or K+, implying that these ions bind equally well to the E1 and E2 conformations. A model is presented for phosphorylation of the ATPase by phosphate as a function of pH, Mg2+, K+ and Ca2+.

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Selected References

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