Effect of malathion on kinetic parameters of acetylcholinesterase (EC 3.1.1.7) in vitro.
Kinetic analysis of the interaction of malathion with camel erythrocyte acetylcholinesterase was investigated in the present study. The Michaelis-Menten constant (K(m)) for the hydrolysis of acetylthiocholine iodide (ASCh) was found to be 53.15 microM and the Vmax was 0.287 mumol/min/mg protein. The Kmapp and Vmaxapp were both decreased by increased malathion concentration. Dixon as well as Lineweaver-Burk plots and their secondary replots indicated that the nature of the inhibition was of the pure uncompetitive type with Ki value estimated as 102.1 ppm. The Kiapp decreased while Vmaxiapp increased by an increased concentration in ASCh.
Kamal
M A
MA
Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia.
D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D002162:Camelus; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D004912:Erythrocytes / Q000201:enzymology; D007700:Kinetics; D008294:Malathion / Q000494:pharmacology*
D002800:Cholinesterase Inhibitors; D000110:Acetylcholinesterase; D008294:Malathion