Metagenomic Profiling of Drinking Water Microbiomes: Insights into Microbial Diversity and Antimicrobial Resistance

Monitoring microbial components in drinking water is as essential as tracking its chemical composition. Although traditional culture-based methods can offer valuable insight into the morphology, behaviour, and phenotype of an organism, their scope is limited to culturable species. With the advent of high-throughput sequencing, we can now detect a wider range of microbes in any ecosystem, gaining more efficient insights into their functional potential and metabolic capabilities. In this study, we performed metagenomic analyses to fully understand the microbiome of drinking water supplied through public distribution systems in an Indian city. Our findings identified bacteria from the phyla Pseudomonadota, Planctomycetota, Bacteroidota, and Actinomycetota, consistent with previous studies of drinking water microbiomes of other countries. We observed that the temperature of the water samples, even as little as a 5°C increase, influenced the composition and diversity of the microbial communities. No significant correlation was detected between the abundance of microbial species and the metal concentration in the sample. In addition, we traced the distribution of antibiotic resistance genes (ARGs), finding widespread resistance to aminoglycosides, tetracyclines, and macrolides across samples. However, the risk associated with these ARGs was beyond the scope of this study. In summary, this research provides a preliminary analysis of the drinking water microbiome, providing a foundation for future management strategies.