Riding the wave of genomics, to investigate aquatic coliphage diversity and activity

Summary Bacteriophages infecting Escherichia coli have been used as a proxy for faecal matter and water quality from a variety of environments. However, the diversity of coliphages that are present in seawater remains largely unknown, with previous studies largely focusing on morphological diversity. Here, we isolated and characterised coliphages from three coastal locations in the UK and Poland. This revealed a surprising genetic diversity, with comparative genomics and phylogenetic analysis of phage isolates facilitating the identification of putative new species within the genera RB69virus and T5virus and a putative new genus within the subfamily Tunavirinae . Furthermore, by combining this genomic data with proteomic and host range analyses a number of phage structural proteins were identified, one of which is likely to be responsible for the observed differences in host range.