Novel Inhibitor of Glutamate-Cysteine Ligase Catalytic Subunit against Tribolium castaneum: High-Throughout Virtual Screening, Molecular Docking and Dynamics Simulation, and Bioassay

The enzyme glutamate-cysteine ligase catalytic subunit (Gclc) is a rate-limiting enzyme in the biosynthesis of glutathione that is involved in antioxidant defense, detoxification of xenobiotics, and/or its metabolites and regulates the cell cycle and immune function. Therefore, Gclc presents an appealing target for the development of novel insecticides. In this study, we conducted high-throughput virtual screening from the ZINC20 database and identified three compounds with high binding affinity to the Tribolium castaneum Gclc (TcGclc). Ultimately, we selected ZINC000032992384 due to its superior stability and lowest binding energy, as determined through molecular dynamics simulations. Bioassay results revealed that the IC₅₀ value of ZINC000032992384 was 19.70 μM lower than that of BSO (49.67 μM). Furthermore, the larval mortality in the ZINC000032992384 treated group was 63.8%, significantly higher than that of the controls (29.1% in the dichlorvos group and 6.4% in the acetone group). This study provides novel insights for the development of a Gclc-targeted inhibitor as a potent insecticide based on the interaction between receptors and ligands.