Metagenomic study focusing on antibiotic resistance genes from the sediments of River Yamuna

Abstract

Antibiotic resistance is one of the major health concerns of the present century. The direct discharge of urban sewage, hospital effluents, and pharmaceutical wastes increases the concentration of antibiotics in riverine ecosystems. This provides selection pressure for the development of novel antibiotic-resistant strains. In this study, metagenomics approach was employed a for constructing a comprehensive profile of the Antibiotic Resistance Genes (ARGs) identified in the sediments of the Yamuna River. A total of 139 ARGs were identified from 39 microbial species. Abundance analysis revealed that, aminoglycoside, beta-lactam, macrolide, and tetracycline resistance genes were highly abundant in the sediment samples obtained from the Yamuna River. The evolutionary relationships among the ARGs were studied by phylogenetic analyses, which revealed that, the identified resistome comprised eight clusters. Network analysis was performed for investigating the broad-spectrum profiles of the ARGs and their enrichment in different biological functions and pathways. Protein-protein interaction (PPI) analyses revealed that, 76, 36, 18, and 5 Gene Ontology (GO)-terms were significantly enriched in Biological process, Molecular Function, Cellular Component, and KEGG Pathways analysis, respectively. The present study elucidates the ecology of microbial antibiotic resistance in the riverine ecosystem of the Yamuna River and provides novel insights into the environmental hotspots that are amenable to the emergence of ARGs in the contaminated riverine hydrosphere.