Plastics entering natural environments rapidly develop microbial biofilms known as the plastisphere, which have emerged as hotspots for antibiotic resistance genes (ARGs). Researchers, including members of the Chinese Academy of Sciences, have highlighted that viruses—among the most abundant biological entities on Earth—may play a key role in transferring these resistance genes between microbes.
Published in the journal Biocontaminant, the study identifies plastisphere viruses as potential hidden drivers of ARG dissemination, mediating horizontal gene transfer, interacting broadly with prokaryotes, and encoding auxiliary metabolic genes (AMGs) that enhance microbial survival under environmental stress.
The plastisphere forms when plastics in ecosystems are colonized by microorganisms, creating dense biofilms that differ from natural habitats. These biofilms facilitate close interactions among bacteria, including pathogens, promoting the exchange of genetic material. The concentration of ARGs and pathogens in the plastisphere increases the potential for the emergence of resistant strains and poses significant risks to public health and the environment.
Viruses within the plastisphere exploit host machinery through lysogenic or lytic cycles. Lysogenic viruses can spread ARGs across broader microbial networks, while lytic viruses may reduce ARG reservoirs by lysing resistant bacteria. Virus-mediated ARG transfer occurs via specialized, generalized, and lateral transduction, with lysogenic viruses particularly enriched in water-based plastispheres. These viral interactions enhance the adaptability of microbial hosts, potentially accelerating the evolution and dissemination of resistance genes.
Plastisphere viruses also carry AMGs that support host survival in stressful conditions, including exposure to pollutants, heavy metals, and antibiotics. These genes not only improve microbial fitness but can intensify ARG accumulation and dissemination. Some viruses encode AMGs involved in nutrient metabolism, biofilm formation, and O-antigen biosynthesis, enhancing pathogen survival and raising the risk of resistant infections.
While the role of viruses in ARG spread remains under-characterized, their interactions with hosts and adaptive infection strategies suggest they may significantly influence antibiotic resistance in plastisphere microbial communities. Methodological challenges, such as contamination during viral sequencing and overestimation of ARG abundance, have complicated assessments of viral contributions. Future research will need to quantify ARG flux between viruses and bacteria, validate the functionality of viral AMGs, and clarify viral infection dynamics to better understand resistance propagation.
This research underscores the plastisphere as more than an environmental nuisance, framing it as a potential driver of antibiotic resistance proliferation. Insights into plastisphere viral ecology could guide environmental monitoring, improve plastic waste management, and inform strategies such as phage therapy to counter the spread of resistant pathogens, integrating viral dynamics into the broader One Health framework.
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