Enantioselective effects of metalaxyl enantiomers on earthworm gut microbiome and antibiotic resistance genes revealed by metagenomic sequencing
The extensive application of chiral fungicides in agricultural systems has raised increasing concerns regarding their ecological impacts, particularly their role in shaping microbial communities and accelerating the spread of antibiotic resistance. Metalaxyl is a widely used systemic chiral fungicide whose enantiomers (R metalaxyl and S metalaxyl) exhibit distinct environmental behaviors and biological effects. However, the enantioselective influence of metalaxyl on soil invertebrate associated microbiomes and antibiotic resistance genes (ARGs) remains poorly understood.In this project, a controlled soil earthworm (Eisenia fetida) microcosm experiment was established to investigate the dissipation, bioaccumulation, and enantioselective ecological effects of racemic metalaxyl and its individual enantiomers. High throughput shotgun metagenomic sequencing was applied to characterize changes in microbial community composition, resistome profiles, and mobile genetic elements (MGEs) in both soil and earthworm gut environments following exposure to different metalaxyl treatments.The dataset reveals pronounced enantioselective behaviors, with S metalaxyl showing substantially higher environmental persistence and inducing a significant increase in gut ARG abundance, while R metalaxyl preferentially accumulated in earthworms and selectively enriched specific ARG types. Plasmid mediated horizontal gene transfer was identified as a major mechanism driving ARG dissemination under metalaxyl stress. These findings highlight the critical role of pesticide chirality in regulating microbial ecology and antibiotic resistance evolution.This BioProject provides a comprehensive metagenomic resource for understanding the interactions among chiral pesticides, soil invertebrates, microbiomes, and antibiotic resistance, and supports improved ecological risk assessment and regulation of chiral agrochemicals.