Characterization of glutathione S-transferase of the rice leaffolder moth, Cnaphalocrocis medinalis (Lepidoptera: Pyralidae): Comparison of its properties of glutathione S-transferases from other lepidopteran insects

• Published in: Pesticide biochemistry and physiology 2008-11, Vol.92 (3), p.125-128
• Main Authors: Yamamoto, Kohji, Teshiba, Satoshi, Aso, Yoichi
• Format: Article
• Language: English
• Subjects: ammonium sulfate; Biological and medical sciences; Cnaphalocrocis medinalis; deltamethrin; enzyme activity; enzyme inhibition; fenitrothion; Fundamental and applied biological sciences. Psychology; Glutathione; Glutathione S-transferase; glutathione transferase; insect pests; Lepidoptera; Lepidopteran insects; Lipid peroxidation; metabolic detoxification; moths; Oryza sativa; permethrin; Phytopathology. Animal pests. Plant and forest protection; plant pests; Protozoa. Invertebrates; purification; Pyralidae
• ISSN: 0048-3575; 1095-9939
• DOI: 10.1016/j.pestbp.2008.07.005

An enzyme that possesses the glutathione S-transferase (GST) activity was found in the rice leaffolder moth, Cnaphalocrocis medinalis. The enzyme was purified to homogeneity for the first time by ammonium sulfate fractionation and affinity chromatography. The resultant enzyme revealed a single band with a molecular mass of 24 kDa by SDS–polyacrylamide gel electrophoresis under reduced conditions. When assayed with 1-chloro-2,4-dinitrobenzene, a universal substrate for GST, the purified GST had an optimum pH at 8.0, and was fairly stable at pH 3–10 and at temperatures below 50 °C. The enzyme was also able to conjugate glutathione to 4-hydroxynonenal, a cytotoxic lipid peroxidation product. The present GST was inhibited by fenitrothion, permethrin, and deltamethrin, suggesting that the GST could be involved in metabolizing these organophosphorus and pyrethroid insecticides.