Diversity and functional roles of viral communities in gene transfer and antibiotic resistance in aquaculture waters and microplastic biofilms.

This study presents a comprehensive metagenomic analysis of viral communities in seawater and microplastic biofilms, uncovering their diversity, functional roles, and ecological significance. We identified 4999 DNA and 22 RNA viral operational taxonomic units. Seawater samples exhibited greater viral diversity, while microplastic biofilms harbored specialized viral assemblages with enriched metabolic functions, particularly in carbohydrate and amino acid metabolism. Auxiliary metabolic genes were detected, suggesting viral involvement in microbial metabolism and nutrient cycling. The dominance of lytic viruses (98 and 100 %) indicates a significant role in microbial regulation. Moreover, antibiotic resistance genes and virulence factors were found, highlighting microplastic biofilms as potential re2servoirs for gene transfer, raising concerns about antibiotic resistance dissemination. The detection of Klebsiella pneumoniae OmpK37 in viruses further underscores the risk of horizontal gene transfer. These findings emphasize the ecological implications of virus-host interactions in marine environments and the urgent need for continued monitoring of viral dynamics in anthropogenically influenced ecosystems.