Occlusion of Na+ by the Na, K-ATPase in the presence of oligomycin
- 29 March 1985
- journal article
- Published by Elsevier BV in Biochemical and Biophysical Research Communications
- Vol. 127 (3), 857-863
- https://doi.org/10.1016/s0006-291x(85)80022-x
Abstract
Oligomycin occludes Na+ in an E1-form of the Na,K-ATPase. The rate constants for the release of Na+ from the E1-form and for the transition to the E2-form are about 0.5 s-1. The effect of oligomycin is not seen using other cations which also have a Na+-like effect on the enzyme conformation. The inhibitory effect of oligomycin on the ADP-ATP dependent Na:Na exchange but not on the accompanying ADP-ATP exchange can be explained from a decrease in the rate of release of Na+ from an E1 approximately phosphoform with Na+ occluded, E'1 approximately P (Na3), i.e. with Na+ in the membrane phase, to an E"1 approximately PNa3 form with Na+ not occluded. E"1 approximately PNa3 is at a step before formation of E2-P, and disappears at a high rate when ADP reacts with E"1 approximately P (Na3).Keywords
This publication has 10 references indexed in Scilit:
- The occlusion of sodium ions within the mammalian sodium‐potassium pump: its role in sodium transport.The Journal of Physiology, 1984
- Kinetics of Na-ATPase activity by the Na,K pump. Interactions of the phosphorylated intermediates with Na+, Tris+, and K+.The Journal of general physiology, 1983
- The effects of Na+ and K+ on the conformational transitions of (Na+ + K+)-ATPaseBiochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1983
- Occlusion of rubidium ions by the sodium‐potassium pump: its implications for the mechanism of potassium transportThe Journal of Physiology, 1982
- The effect of pH, of ATP and of modification with pyridoxal 5-phosphate on the conformational transition between the Na+-form and the K+-form of theBiochimica et Biophysica Acta (BBA) - Biomembranes, 1982
- Effects of ATP and protons on the Na : K selectivity of the (Na+ + K+)-ATPase studied by ligand effects on intrinsic and extrinsic fluorescenceBiochimica et Biophysica Acta (BBA) - Biomembranes, 1980
- Preparation of membrane-bound and of solubilized from rectal glands of Squalus acanthias. The effect of preparative procedures on purity, specific and molar activityBiochimica et Biophysica Acta (BBA) - Enzymology, 1979
- A simplified method for analysis of inorganic phosphate in the presence of interfering substancesAnalytical Biochemistry, 1978
- Ouabain-binding and phosphorylation of (Na++K+)ATPase treated with N-ethylmaleimide or oligomycinBiochimica et Biophysica Acta (BBA) - Enzymology, 1976
- The stoicheiometry of the sodium pumpThe Journal of Physiology, 1967