ISOLATION AND PARTIAL-PURIFICATION OF ACETYLCHOLINESTERASE FROM LYGUS-HESPERUS (HEMIPTERA, MIRIDAE)

Acetylcholinesterase (AChE) from Lygus hesperus Knight was isolated and partially purified by Triton X-100 extraction, ammonium sulfate precipitation, gel filtration, and affinity chromatography. The degree of the purification was about 1,400-fold and the yield was about 3.3%. Purification was primarily the result of affinity chromatography, and the low recovery was due to sequential loss of AChE in each step during purification. The solubility of AChE can be greatly enhanced by addition of Triton X-100 but not by high ionic strength, suggesting that L. hesperus contains little or no asymmetric forms of AChE. The procedure is evaluated, and the possibility of increasing the yield is also discussed.