ABSTRACT
The rat liver microsomal glutathione transferase was activated by N-ethylmaleimide, solubilized by Triton X-100 and purified by chromatography on hydroxyapatite and CM Sephadex C-50. A 28-fold purification resulted in a 38% yield. The purified protein moved as a band with an apparent molecular weight of 14,000 on sodium dodecyl sulphate polyacrylamide gel electrophoresis and appeared to be nearly homogeneous. The N-terminal amino acid of the purified enzyme was alanine, identified by the dansyl method. Optimum pH and temperature were 6.8 and 30 degrees C, respectively.
Subject(s)
Glutathione Transferase/isolation & purification , Microsomes, Liver/enzymology , Animals , Electrophoresis, Polyacrylamide Gel , Male , Rats , Rats, Inbred StrainsABSTRACT
Methyl-ISP, a newly developed organophosphorous insecticide, is used in China to treat and protect plants from pest infestation. Our studies demonstrated that methyl-ISP is metabolized rapidly in rat and mouse. Its toxicity was low, no obvious accumulative toxicity, chronic toxicity, teratogenicity, mutagenicity, reproductive toxicity or delayed neurotoxicity could be observed. It is therefore concluded that methyl-ISP is relatively safe to animals and human subjects. methyl-ISP is now employed to replace the other commonly used insecticide hexachlorobenzene (666) in agriculture. A preliminary study was performed to elucidate the mechanism of intoxication at subcellular levels.
