Purification and studies on characteristics of cholinesterases from Daphnia magna

作     者：Yan-xia YANG Li-zhi NIU Shao-nan LI 

作者机构：Institute of Pesticide and Environmental ToxicologyCollege of Agriculture and BiotechnologyZhejiang University 

出 版 物：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 (浙江大学学报（英文版）B辑（生物医学与生物技术）)

年 卷 期：2013年第14卷第4期

页      面：325-335页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 

基　　金：Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY12B07008) the Department of Education of Zhejiang Province,China(No.20070138) 

主　　题：Crustacea Pseudocholinesterase Cholinesterase Substrate preference Selective inhibitors 

摘      要：Due to their significant value in both economy and ecology,Daphnia had long been employed to investigate in vivo response of cholinesterase(ChE) in anticholinesterase exposures,whereas the type constitution and property of the enzyme remained unclear.A type of ChE was purified from Daphnia magna using a three-step procedure,i.e.,Triton X-100 extraction,ammonium sulfate precipitation,and diethylaminoethyl(DEAE)-Sepharose Fast-Flow *** to sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE),molecular mass of the purified ChE was estimated to be 84 *** on substrate studies,the purified enzyme preferred butyrylthiocholine iodide(BTCh) [with maximum velocity(Vmax)/Michaelis constant(Km)=8.428 L/(min·mg protein)] to acetylthiocholine iodide(ATCh) [with V max /Km =5.346 L/(min·mg protein)] as its *** of the purified enzyme was suppressed by high concentrations of either ATCh or *** studies showed that the purified enzyme was more sensitive towards inhibition by tetraisopropylpyrophosphoramide(iso-OMPA) than by 1,5-bis(4-allyldimethylammoniumphenyl) pentan-3-one dibromide(BW284C51).Result of the study suggested that the purified ChE was more like a type of pseudocholinesterase,and it also suggested that Daphnia magna contained multiple types of ChE in their bodies.