title: Development of ESI-MS-based continuous enzymatic assay for real-time monitoring of enzymatic reactions of acetylcholinesterase.
abstract: The continuous enzymatic assay based on ESI-MS was developed to real-time monitoring of enzymatic reactions of acetylcholinesterase (AChE). The changes of product concentrations were continuously measured. Calibration curves were established for quantitative calculation. By this method, the Michaelis constant (Km) of acetylcholinesterase was determined to be 70.60±0.93μM and Huperzine A as an effective inhibitor of acetylcholinesterase displayed a mixed inhibition with competitive and noncompetitive inhibition behaviors. The half maximal inhibitory concentration (IC50) and inhibition constant (Ki) value of Huperzine A were also calculated as 48.51±1.16nM and 26.73±0.27nM, respectively. This method provides the rapid and accurate ways to monitor enzyme reactions.
authors: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China; University of the Chinese Academy of Sciences, Beijing 100049, China.
authors: Qiang
authors: Q
authors: Fu
authors: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China; University of the Chinese Academy of Sciences, Beijing 100049, China.
authors: Jun
authors: J
authors: Tang
authors: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China; Key Laboratory of Synthetic Rubber of Chinese Academy of Sciences, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China. Electronic address: cuimeng@ciac.ac.cn.
authors: Meng
authors: M
authors: Cui
authors: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China.
authors: Zhong
authors: Z
authors: Zheng
authors: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China.
authors: Zhiqiang
authors: Z
authors: Liu
authors: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China.
authors: Shuying
authors: S
authors: Liu
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D002800:Cholinesterase Inhibitors / Q000032:analysis* / Q000378:metabolism*; D057075:Enzyme Assays / Q000379:methods*; D004800:Enzymes, Immobilized / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D007700:Kinetics; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D002800:Cholinesterase Inhibitors; D004800:Enzymes, Immobilized; D000110:Acetylcholinesterase
keywords: Continuous enzymatic assay; ESI-MS; Half maximal inhibitory concentration (IC50); Inhibition constant (Ki); Michaelis constant (Km)