Antibiotic resistome in the glacier forelands of polar regions.

UNLABELLED: Antibiotic resistance genes (ARGs) pose a significant threat, exacerbated by climate change impacts on polar regions, particularly melting glaciers and permafrost. While ancient antibiotic resistance exists in the environments, the release and dissemination of ARGs remain poorly understood. This study investigated ARG composition and distribution in 43 metagenomes from Arctic and Antarctic glacier forelands. We identified 154 ARGs, predominantly bacitracin resistance, followed by rifamycin, fosfomycin, vancomycin, tetracycline, and beta-lactam resistance genes. Significant correlations were observed between ARGs and mobile genetic elements (MGEs), with 20 ARGs associated with tnpA MGEs. Actinomycetota and Pseudomonadota were the primary ARG-carrying phyla. Metagenome-assembled genomes revealed Mycobacterium sp., Pseudomonas sp., and Tatlockia sp. as major ARG-harboring pathogens in the glacier forelands. Evolutionarily adapted, distinct ancient ARGs were abundant in the polar environments, varying between different geographic regions. The environmental parameters such as pH and total organic carbon significantly influenced the ARG distribution in the Arctic and Antarctic glacier forelands. This study provides crucial baseline data on antimicrobial resistance, highlighting potential risks associated with rapid environmental change in the regions.

IMPORTANCE: Antibiotic resistance poses a significant global health threat, exacerbated by the release of antibiotic resistance genes from melting glaciers and permafrost due to climate change. This study provides crucial baseline data on the composition and distribution of antibiotic resistance genes in these vulnerable polar environments, which is essential for understanding and mitigating the risks associated with their release. The findings have far-reaching implications for global health security and emphasize the need for further research to address this emerging threat.