Reversible oxidative stress mediates microplastic-induced inhibition and resilience in the sulfate-reducing microbiome system under antibiotic exposure

This study examined how polyethylene microplastics (PE MPs) affect sulfamethoxazole (SMX) degradation in anaerobic sulfur-driven systems using physiological assays and metagenomics. PE MPs significantly reduced SMX removal and transiently impaired sulfur-driven functions, with metagenomics revealing decreased abundance and expression of sulfur metabolism genes. Notably, upon PE MP removal, both SMX degradation and sulfur metabolic functions rapidly recovered, indicating reversible rather than permanent functional impairment. These findings demonstrate that microbial community functional plasticity and redox-regulated resilience are key mechanisms maintaining process stability under microplastic-antibiotic co-stress in engineered anaerobic systems..