ACETYLCHOLINESTERASE FROM DESERT COBRA (WALTERINNESIA-AEGYPTIA) VENOM- OPTIMIZATION AND KINETICS STUDY

Acetylcholinesterase (AChE) was investigated in Walterinnesia aegyptia venom and characterized with respect to its kinetic properties. It wa s found that 4.0 ug of crude venom protein and an incubation time of 4 .0 min were suitable conditions for linearity of AChE activity at 25 d egrees C. The optimum strength of the sodium phosphate buffer was 0.05 M, and the optimum pH was 7.75. The optimum temperature was 30 degree s C. The activation energy and the heat of activation were observed to be 6510 and 5922 cal/mole. The AChE was specific for acetylthiocholin e but it did not hydrolyse butyrylthiocholine. The optimum substrate c oncentration was 3.0 mM but at higher substrate concentrations, the AC hE activity declined. The ASCh concentration ranges for different orde rs of the reactions were determined and kinetic parameters (K-m, V-max , k(cat), and k(sp)) were established at each order of the reaction.