Functional metagenomics reveals novel antibiotic resistomes in polar soils.

Using a robust functional metagenomics approach, we demonstrated that polar environments are important reservoirs of novel antibiotic resistance genes (ARGs). DNA was initially extracted from cultured bacterial consortia in the polar soils and recombined into plasmid vectors and then transformed into Escherichia coli (E. coli) for the subsequent screening of antibiotic resistance. Consequently, we identified 671 novel polar ARGs with experimentally verified resistance against multiple clinical antibiotics (cefotaxime, folate synthesis inhibitors, and clindamycin). Bioinformatics analysis revealed that novel polar ARGs had limited mobility and dissemination potential and were seldom carried by human bacterial pathogens. Overall, this study offers a comprehensive perspective on previously overlooked novel ARGs in polar regions, advancing our understanding of environmental resistomes.