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bioRxiv · 10.1101/2021.09.29.462415

Structure and function of one unclassified-class glutathione S-transferase in Leptinotarsa decemlineata

Liu, Y.·Moural, T. W.·Koirala, S. B.·Hernandez, J.·Shen, Z.·Alyokhin, A.·Zhu, F.
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Abstract

Arthropod Glutathione S-transferases (GSTs) constitute a large family of multifunctional enzymes that are mainly associated with xenobiotic or stress adaptation. GST-mediated xenobiotic adaptation is through direct metabolism or sequestration of xenobiotics, and/or indirectly by providing protection against oxidative stress induced by xenobiotic exposure. To date, the roles of GSTs in xenobiotic adaptation in the Colorado potato beetle (CPB), a notorious agriculture pest of plants within Solanaceae have not been well studied. Here, we functionally expressed and characterized an unclassified-class GST, LdGSTu1. The three-dimensional structure of the LdGSTu1 was solved with a resolution up to 1.8 [A] by x-ray crystallography. Recombinant LdGSTu1 was used to determine enzyme activity and kinetic parameters using 1-chloro-2,4-dinitrobenzene (CDNB), GSH, p-nitrophenyl acetate (PNA) as substrates. The enzyme kinetic parameters and enzyme-substrate interaction studies demonstrated that LdGSTu1 could catalyze the conjugation of GSH to both CDNB and PNA, with a higher turnover number for CDNB than PNA. The LdGSTu1 enzyme inhibition assays demonstrated that the enzymatic conjugation of GSH to CDNB could be inhibited by multiple pesticides, suggesting a potential function of LdGSTu1 in xenobiotic adaptation.

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Liu, Y., Moural, T. W., Koirala, S. B., Hernandez, J., Shen, Z., Alyokhin, A., Zhu, F.. 2021-09-29. Structure and function of one unclassified-class glutathione S-transferase in Leptinotarsa decemlineata. https://doi.org/10.1101/2021.09.29.462415

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