[Effect of calmodulin on myometrial cell membrane Ca2+,Mg2+-ATPase activity].
Myometrium cell plasma membrane Ca2+, Mg(2+)-ATPase purified by an affinity chromatography on calmodulin-sepharose 4B is calmodulin-dependent enzyme. Concentration of calmodulin required for half-maximal activation of enzyme was about 26 nM. By unlike to the enzymes originated from other tissues sensitivity to the calmodulin of the myometrial sarcolemma Ca(2+)-transporting ATPase was lower: calmodulin increased Vmax of ATPase about 1.25-fold, the apparent constant of the activation of enzyme by Ca2+ failed to alter independently on the phospholipid presenting at the enzyme isolation.
Slinchenko
N M
NM
Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv. kinet@biochem.kiev.ua
D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism*; D002147:Calmodulin / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D002846:Chromatography, Affinity; D004789:Enzyme Activation; D005260:Female; D007700:Kinetics; D009215:Myometrium / Q000187:drug effects* / Q000201:enzymology; D010743:Phospholipids / Q000378:metabolism
D002147:Calmodulin; D010743:Phospholipids; D017301:Ca(2+) Mg(2+)-ATPase