Gimmel'reĭkh N G, Kravets L G, Popova G N, Kurskiĭ M D
Biokhimiia. 1978 Mar;43(3):481-7.
Ca2+-ATPase of skeletal muscle sarcolemma has been isolated and purified. It is prepared from salt extract of sarcolemma by ammonium sulfate fractionation and further purified by gel chromatography on Sepharose 4B. The purity of preparations was evaluated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. It has been shown that Ca2+-ATPase possesses the same mobility as skeletal muscle myosin under gel chromatography on Sepharose 4B and the same mobility as myosin heavy chains in sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Membrane protein binds to rabbit skeletal muscle actin, and this complex dissociates by ATP. Interaction with actin does not change Ca2+- or Mg2+-stimulated ATPase activity. Enzyme has only one pH optimum at 7,0-7,6. Membrane protein is highly specified to calcium--ATPase activity in the presence of Mn2+ is 10% and in the presence of Sr2+, Mg2+ or Co2+ are 3-5% of the activity in the presence of Ca2+. Other nucleoside triphosphate (UTP and ITP) are hydrolyzed at lower rates than is ATP.
骨骼肌肌膜的Ca2 + -ATP酶已被分离和纯化。它是从肌膜的盐提取物中通过硫酸铵分级分离制备的，并通过在琼脂糖4B上的凝胶色谱进一步纯化。制备物的纯度通过十二烷基硫酸钠聚丙烯酰胺凝胶电泳进行评估。结果表明，在琼脂糖4B凝胶色谱中，Ca2 + -ATP酶与骨骼肌肌球蛋白具有相同的迁移率，在十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳中与肌球蛋白重链具有相同的迁移率。膜蛋白与兔骨骼肌肌动蛋白结合，并且这种复合物通过ATP解离。与肌动蛋白的相互作用不会改变Ca2 +或Mg2 +刺激的ATP酶活性。酶在7.0 - 7.6时只有一个最适pH值。膜蛋白对钙 - ATP酶活性具有高度特异性，在存在Mn2 +时活性为10％，在存在Sr2 +、Mg2 +或Co2 +时活性为存在Ca2 +时活性的3 - 5％。其他核苷三磷酸（UTP和ITP）的水解速率低于ATP。
