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Updated: Aug 12, 2026

Functional Reconstitution and Channel Activity Measurements of Purified Wildtype and Mutant CFTR Protein
Published on: March 9, 2015
Phosphorylation of chloride-ATPase reconstituted from Aplysia gut
1Department of Physiology, College of Medicine, University of Florida, Gainesville, Florida 32610, USA. gag@phys.med.ufl.edu
Abstract:
The present study was primarily done to compare cation-ATPase phosphorylation kinetics with an anion-ATPase's phosphorylation kinetics because of the paucity of information in this area. Utilizing a proteolipsomal preparation containing Cl(-)-ATPase from Aplysia gut, it was demonstrated that phosphorylation of this P-type ATPase was absolutely dependent upon Mg(2+). In organic phosphate concentrations directly (P(i)) enhanced phosphoprotein formation in the presence of increasing concentrations of Mg(2+). It was also shown that the calculated rate constant for E(1)-P formation was 26/sec. This approximated E(1)-P rate constant values for other electrogenic, uniport P-type ATPases, and therefore it was concluded from the results that the anion-ATPase phosphorylation kinetics did not greatly differ from cation-ATPase phosphorylation kinetics.
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