Exploration of activated sludge resistome using metagenomics

Area of Science:

• Environmental microbiology
• Genomics
• Public health

Background:

• Antibiotic resistance is a critical global health challenge.
• Poor waste management and sanitation in India exacerbate antimicrobial resistance (AMR) dissemination.
• Microbial biodiversity is a key source of pharmaceutical compounds.

Purpose of the Study:

• To conduct surveillance of antibiotic resistance genes (ARGs), drug-resistant microbes, and mobile genetic elements (MGEs).
• To analyze two activated sludge metagenome samples from Ankleshwar, Gujarat, India.
• To understand the role of MGEs in AMR spread via horizontal gene transfer.

Main Methods:

• Metagenomic approach for DNA sequencing and analysis.
• Identification of ARGs, resistant bacteria, and MGEs.
• Statistical analysis using STAMP software.

Main Results:

• Proteobacteria identified as the most abundant bacterial phylum.
• Discovery of 24 genes conferring resistance to antibiotics and heavy metals.
• Abundance of multidrug-resistant ESKAPE pathogens and MGEs like IncP-1 plasmids.
• Detection of gene transfer agents, phages, and prophages.

Conclusions:

• Activated sludge metagenomes harbor significant antibiotic resistance determinants.
• MGEs, including plasmids and phages, are prevalent and likely facilitate AMR dissemination.
• Metagenomic surveillance is crucial for understanding AMR in environmental settings.