Detoxification enzyme modulation and larvicidal efficacy of Klebsiella pneumoniae (PX652414) and Proteus mirabilis (PZ337687) metabolites in mosquito vectors

Abstract Mosquitoes of the Anopheles , Aedes , and Culex genera serve as vectors for significant human and animal diseases. The increasing prevalence of insecticide resistance, primarily mediated by detoxification enzymes, highlights the urgent need for innovative biocontrol strategies. This study assessed the larvicidal activity of secondary metabolites produced by Klebsiella pneumoniae PX652414 and Proteus mirabilis PZ337687, as well as their impact on esterase and glutathione-S-transferase (GST) enzyme activities in three major mosquito species: An. gambiae s.l., Ae. aegypti , and Cx. quinquefasciatus . Metabolites incubated for three and eight days were individually applied to separate cohorts of mosquito larvae. Larval mortality, lethal concentrations (LCs), and enzyme activities were evaluated following 72 hours of exposure. K. pneumoniae metabolites induced substantial larval mortality across all mosquito species, demonstrated by low LC50 values and decreased esterase and GST activity, particularly in Cx. quinquefasciatus. Conversely, P. mirabilis metabolites resulted in minimal mortality and elevated esterase and GST activity. These results demonstrate enzyme modulation by these metabolites and indicate that K. pneumoniae (PX652414) metabolites may serve as promising agents for integrated vector management.