Tikunov B A
Biokhimiia. 1990 May;55(5):822-8.
The effect of magnesium ions on the two-stage kinetics of superprecipitation (SPP) and ATP activity of natural skeletal muscle actomyosin was studied. It was found that the changes in the ratios of two independent steps of SPP and ATPase activity are mainly induced by the Mg-ATP2- complex, but not by free Mg2+. These changes in the kinetics of SPP and ATPase are regarded as being due to the shift in the dynamic equilibrium between the two types of the actomyosin complexes in solution, each of which is characterized by different reaction mechanisms. The role of the Mg-ATP2(-)-induced alteration of at least two structural-and-functional states of actomyosin in muscle contractibility is discussed.
研究了镁离子对天然骨骼肌肌动球蛋白超沉淀（SPP）的两阶段动力学和ATP活性的影响。发现SPP两个独立步骤的比率变化和ATP酶活性主要由Mg-ATP2-复合物诱导，而非游离Mg2+。SPP和ATP酶动力学的这些变化被认为是由于溶液中两种肌动球蛋白复合物之间动态平衡的改变，每种复合物具有不同的反应机制。讨论了Mg-ATP2(-)诱导的肌动球蛋白至少两种结构和功能状态改变在肌肉收缩性中的作用。
