Ca2+-stimulated, Mg2+-dependent ATPase in bovine thyroid plasma membranes.
An isolated plasma membrane fraction from bovine thyroid glands contained a Ca2+-stimulated, Mg2+-dependent adenosine triphosphatase ((Ca2+ + Mg2+)-ATPase) activity which was purified in parallel to (Na+ + K+)-ATPase and adenylate cyclase. The (Ca2+ + Mg2+)-ATPase activity was maximally stimulated by approx. 200 microM added calcium in the presence of approx. 200 microM EGTA (69.7 +/- 5.2 nmol/mg protein per min). In EGTA-washed membranes, the enzyme was stimulated by calmodulin and inhibited by trifluoperazine.
D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase; D002118:Calcium / Q000494:pharmacology; D000252:Calcium-Transporting ATPases / Q000302:isolation & purification / Q000378:metabolism*; D002147:Calmodulin / Q000494:pharmacology; D002417:Cattle; D002462:Cell Membrane / Q000201:enzymology; D007700:Kinetics; D013961:Thyroid Gland / Q000201:enzymology*
D002147:Calmodulin; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D002118:Calcium