When designing treatment processes to ensure safe drinking water, engineers have focused on removing human pathogens and have ignored the role that bacteriophages may play in regulating communities of harmful bacteria, such as mycobacteria. As mycobacteria and other opportunistic pathogens in drinking water cause an increasing number of infections in the US, it is clear that new treatment methods are needed. Harnessing mycobacteriophages is one intriguing new solution for controlling mycobacteria growth in drinking water. To develop such a technology, it is necessary to first understand the interactions between bacteria and viruses in drinking water systems. In this presentation, I will cover my approaches to determine the abundances and types of viruses present in drinking water. I will discuss my work mining bacteriophage sequences from existing drinking water metagenomes that were designed to characterize bacterial abundance in drinking water distribution systems. Mining these assemblies for viral sequences revealed that on average 9.6 +/- 12.1% of contigs are viral. Further, drinking water metagenomes taken from distribution systems that use residual disinfectants (such as chlorine) have a higher proportion of viral contigs than systems that do not use a residual disinfectant (p=0.003). While we can discover useful information about the drinking water virome from these existing studies, each collected their biomass on 0.22µm filters that most viruses can pass through. In order to understand whether the viral diversity reflected in previous studies is representative of DNA viruses in drinking water, I am also developing techniques to concentrate viruses from drinking water. Altogether, this research will expand our understanding of phage-host interactions and is critical to assess the feasibility of designing a bacteriophage-based method for controlling opportunistic pathogen levels in drinking water systems.
Speaker Profile: https://envbiotech.engin.umich.edu/profile/1066/