An optimized micro-assay of myosin II ATPase activity based on the molybdenum blue method and its application in screening natural product inhibitors

作者：Chen Hong-Lin; Zhao Jing; Zhang Guan-Jun; Kou Jun-Ping^*; Yu Bo-Yang

来源：Chinese Journal of Natural Medicines, 2016, 14(6): 421-426.

DOI：10.1016/s1875-5364(16)30038-3

• Myosin II ATPase activity
• Blebbistatin
• Bioluminescence
• Natural products
• Malachite green

Myosin II plays multiple roles in physiological and pathological functions through its ATPase activity. The present study was designed to optimize a micro-assay of myosin II ATPase activity based on molybdenum blue method, using a known myosin II ATPase inhibitor, blebbistatin. Several parameters were observed in the enzymatic reaction procedure, including the concentrations of the substrate (ATP) and calcium chloride, pH, and the reaction and incubation times. The proportion of coloration agent was also investigated. The sensitivity of this assay was compared with the malachite green method and bioluminescence method. Additionally, 20 natural compounds were studied for myosin II ATPase inhibitory activity using the optimized method. Our results showed that ATP at the concentration of 5 mmol.L-1 and ammonium molybdate : stannous chloride at the ratio of 15 : 1 could greatly improve the sensitivity of this method. The IC50 of blebbistatin obtained by this method was consistent with literature. Compound 8 was screened with inhibitory activity on myosin II ATPase. The optimized method showed similar accuracy, lower detecting limit, and wider linear range, which could be a promising approach to screening myosin II ATPase inhibitors in vitro.

• 出版日期2016-6
• 单位中国药科大学