Antimicrobial Resistance in Aquatic Ecosystems: Microbial Community Responses to Co-occurring Pharmaceutical, Heavy Metal, and Microplastic Stressors

Aquatic ecosystems are increasingly exposed to complex mixtures of emerging contaminants originating from agricultural, industrial, and urban sources. These contaminants include pharmaceuticals, heavy metals, and microplastics, which can exert overlapping and interacting pressures on aquatic microbial communities. Antibiotic-driven selection pressure is a major driver of antimicrobial resistance (AMR), while co-occurring stressors may independently or synergistically reinforce the persistence and dissemination of resistance determinants. Heavy metals can co-select for antibiotic-resistance genes (ARGs), which are frequently co-located with metal-resistance genes on shared mobile genetic elements. Microplastics can provide surfaces for biofilm formation and create “plastisphere” hotspots that facilitate the horizontal transfer of resistance determinants among bacterial populations. Beyond antibiotics, non-antibiotic pharmaceutical contaminants, including nonsteroidal anti-inflammatory drugs (NSAIDs) and H2-receptor antagonists, can exert distinct selective and metabolic pressures on native microbial populations, shaping community-level biodegradation capacity and functional adaptation independently of resistance dynamics. Although the environmental fate of these contaminants has received growing attention, the responses, adaptations, and functional shifts of native microbial communities, including bacteria, archaea, and microbial eukaryotes, that drive these multi stressor interactions remain comparatively underexplored.This Research Topic aims to advance understanding of how aquatic microbial communities perceive, adapt to, and are functionally reshaped by co-occurring contaminant pressures. We particularly welcome studies employing genomic, metagenomic, transcriptomic, and physiological approaches to elucidate natural biodegradation pathways, resistome dynamics, and community level adaptation mechanisms in freshwater, estuarine, and marine systems. Contributions addressing the interactions among antibiotics, heavy metals, microplastics, and non antibiotic pharmaceutical contaminants are especially encouraged, as are studies linking contaminant exposure to changes in microbial community structure, functional activity, biodegradation capacity, and resistance dissemination.To gather further insights into microbial responses to contaminant mixtures in aquatic environments, we welcome contributions addressing, but not limited to, the following themes:- Responses and adaptations of native bacteria, archaea, and microbial eukaryotes to co-occurring contaminant pressures- Natural biodegradation pathways and community level functional adaptation- Resistome persistence and dissemination in freshwater, estuarine, and marine systems- Co-selection of antibiotic resistance genes and metal resistance genes on shared mobile genetic elements- Microplastic associated biofilms, plastisphere hotspots, and horizontal gene transfer of resistance determinants- Selective and metabolic effects of non-antibiotic pharmaceuticals, including NSAIDs and H2-receptor antagonists- Genomic, metagenomic, transcriptomic, and physiological approaches to aquatic microbial ecology under contaminant exposureAs a secondary theme, we welcome studies of engineered or bioreactor based remediation systems, such as biochar based sorbents and membrane bioreactors, only where microbial findings are explicitly linked to, or directly extrapolated to, microbial ecology and function in natural aquatic systems. Such submissions must characterize the microbial community or its functional response using taxonomic, genomic, metagenomic, transcriptomic, or activity based measurements, and must clearly explain how the findings inform the behavior of native microbial assemblages in freshwater, estuarine, or marine environments. Studies reporting engineering performance metrics alone, including removal efficiency, sorption capacity, or reactor optimization, or invoking natural systems only in general terms fall outside the scope of this Research Topic. Topic editors: SANDIP MONDAL, Naga Raju Maddela, Manish Kumar Gautam Source: https://www.frontiersin.org/research-topics/84906/antimicrobial-resistance-in-aquatic-ecosystems-microbial-community-responses-to-co-occurring-pharmaceutical-heavy-metal-and-microplastic-stressors