Barnes J A, King M J, Kalra J, Sharma R K
Department of Pathology, University of Saskatchewan, Royal University Hospital, Saskatoon, Canada.
Biochem Biophys Res Commun. 1992 Jul 31;186(2):819-26. doi: 10.1016/0006-291x(92)90819-7.
A novel calmodulin-dependent protein kinase has been isolated from bovine cardiac muscle by successive chromatography on DEAE-Sepharose 6B, Calmodulin-Sepharose 4B affinity and Sepharose 6B chromatography columns. The protein kinase was shown by gel filtration chromatography to have a molecular mass of 36,000 daltons. The highly purified protein kinase stoichiometrically phosphorylated the high molecular weight calmodulin-binding protein from cardiac muscle [Sharma RK (1990) J Biol Chem 265, 1152-1157] in a Ca2+/calmodulin-dependent manner. The phosphorylation resulted in the maximal incorporation of 1 mol of phosphate/mol of the high molecular weight calmodulin-binding protein. Other Ca2+/calmodulin-dependent protein kinases failed to phosphorylate the high molecular weight calmodulin-binding protein. The distinct substrate specificity of this protein kinase indicates that it is not related to the known calmodulin-dependent protein kinases and therefore constitutes a novel protein kinase.
通过在DEAE-琼脂糖6B、钙调蛋白-琼脂糖4B亲和柱和琼脂糖6B色谱柱上连续层析，从牛心肌中分离出一种新型钙调蛋白依赖性蛋白激酶。凝胶过滤色谱显示该蛋白激酶的分子量为36,000道尔顿。高度纯化的蛋白激酶以Ca2+/钙调蛋白依赖性方式化学计量地磷酸化心肌中的高分子量钙调蛋白结合蛋白[Sharma RK(1990)J Biol Chem 265,1152 - 1157]。磷酸化导致每摩尔高分子量钙调蛋白结合蛋白最大掺入1摩尔磷酸盐。其他Ca2+/钙调蛋白依赖性蛋白激酶未能磷酸化高分子量钙调蛋白结合蛋白。这种蛋白激酶独特的底物特异性表明它与已知的钙调蛋白依赖性蛋白激酶无关，因此构成一种新型蛋白激酶。
