ABSTRACT
The studies on binding of hexachlorocyclohexane (HCH) with carrier proteins were carried out to establish the role of proteins in the transport of insecticides in insects. Sephadex G-200 column chromatography resolved haemolymph of adult male desert locust, Schistocerca gregaria into three major protein peaks. There was significant binding of gamma-HCH with first protein peak (F1). Two classes of binding sites were observed on first protein peak for gamma-HCH. However low level of binding was observed with the third protein peak (F3) of the haemolymph. Bindings of HCH-isomers (alpha, beta and gamma) with bovine serum albumin (BSA) were not related to their water solubilities. Moderate to low affinities (1.4 -1.84 x 10(6) M(-1)) of HCH-isomers for BSA were observed. The present studies showed that more HCH binds to haemolymph lipoprotein of locust as compared to BSA. This indicates a significant role of haemolymph proteins in the transport of insecticides in insects.
Subject(s)
Animals , Cats , Grasshoppers , Insect Proteins/physiology , Isomerism , Hexachlorocyclohexane/chemistryABSTRACT
Normal coordinate analysis has been made for gammexane using the Wilson's G-F matrix method with Urey-Bradley force field. Molecular orbital calculations using CNDO/2 method have also been carried out for the five isomers of hexachlorocyclohexane to give the valence charge densities on the atoms of the molecules. A toxicity parameter that takes into account a shape factor and the valence charge density on the atoms has been defined. On the toxicity scale so defined the gamma-isomer alone has a significant value.