Abundance, diversity and mobility potential of antibiotic resistance genes in pristine Tibetan plateau soi as revealed by soil metagenomics.
Widespread occurrence of antibiotic resistance genes (ARGs) has become an important clinical issue. Studying ARGs in pristine soil environments can help better understand the intrinsic soil resistome. In this study, ten soil samples were collected from a high elevation and relative pristine Tibetan area, and metagenomic sequencing and bioinformatic analyses were conducted to investigate the microbial diversity, the abundance and diversity of ARGs, and the mobility potential of ARGs as indicated by different mobile genetic elements (MGEs). A total of 48 ARG types with relative abundance of 0.05-0.28 copies of ARG/copy of 16S rRNA genes were detected in Tibetan soil samples. The observed ARGs were mainly associated with antibiotics including glycopeptide and rifamycin; the most abundant ARGs were vanRO and vanSO. Low abundance of MGEs and potential plasmid-related ARGs indicated low horizontal gene transfer (HGT) risk of ARGs in the pristine soil. Pearson correlation and redundancy analyses showed that temperature and total organic carbon (TOC) were the major environmental factors controlling both microbial diversity and ARG abundance and diversity.