Binding of green tea epigallocatechin gallate to the arginine kinase active site from the brown recluse spider (): A potential synergist to chemical pesticides.

spp. spiders can cause serious public health issues. Chemical control is commonly used, leading to health and environmental problems. Identifying molecular targets and using them with natural compounds can help develop safer and eco-friendlier biopesticides. We studied the kinetics and predicted structural characteristics of arginine kinase (EC 2.7.3.3) from (AK), a key enzyme in the energy metabolism of these organisms. Additionally, we explored (-)-epigallocatechin gallate (EGCG), a green tea flavonoid, as a potential lead compound for the AK active site through fluorescence and analysis, such as molecular docking and molecular dynamics (MD) simulation and MM/PBSA analyses. The results indicate that AK is a highly efficient enzyme ( 0.14 mM, 0.98 mM, 93 s, / 630 s mM, / 94 s mM), which correlates with its structure similarity to others AKs (such as , , and ) and might be related to its important function in the spider's energetic metabolism. Furthermore, the MD and MM/PBSA analysis suggests that EGCG interacted with AK, specifically at ATP/ADP binding site (RMSD <1 nm) and its interaction is energetically favored for its binding stability (-40 to -15 kcal/mol). Moreover, these results are supported by fluorescence quenching analysis ( 58.3 μM and 1.71 × 10 M). In this context, AK is a promising target for the chemical control of , and EGCG could be used in combination with conventional pesticides to manage the population of species in urban areas.