Fasolo M, Cavallini P, Dalla Libera L
National Research Council Unit for Muscle Biology and Physiopathology, Institute of General Pathology, Padova, Italy.
Biochem Biophys Res Commun. 1991 Feb 28;175(1):277-84. doi: 10.1016/s0006-291x(05)81231-8.
When smooth muscle myosin light chain kinase, purified by standard procedures from chicken gizzard smooth muscle, was applied to an anion-exchange high-performance liquid chromatographic column, three well resolved peaks were obtained. Each peak contained a single protein whose electrophoretic mobility corresponded to that of MLCK. However each enzyme was characterized by a different specific activity. Peptide mapping experiments were unable to demonstrate different proteolytic patterns for the three proteins. Treatment of myosin light chain kinase with alkaline phosphatase, prior to ion chromatography, resulted in a change of elution profile. These experiments suggest that myosin light chain kinase could exist in three forms characterized by a different degree of phosphorylation.
当通过标准程序从鸡砂囊平滑肌中纯化得到的平滑肌肌球蛋白轻链激酶应用于阴离子交换高效液相色谱柱时，获得了三个分离良好的峰。每个峰都包含一种单一蛋白质，其电泳迁移率与肌球蛋白轻链激酶的迁移率相对应。然而，每种酶的特征在于不同的比活性。肽图谱实验无法证明这三种蛋白质具有不同的蛋白水解模式。在离子色谱之前用碱性磷酸酶处理肌球蛋白轻链激酶，导致洗脱图谱发生变化。这些实验表明，肌球蛋白轻链激酶可能以三种具有不同磷酸化程度的形式存在。
