Organism

The first sequenced genome was the Escherichia virus phiX174 (Sanger, et al. Nature 1977). In the years since, many more viruses infecting E. coli have been characterized and sequenced. The differences between these viruses are considerable, and their interactions with their host and each other are some of the best understood biological systems in the world. Nevertheless, this group of organisms is constantly yielding new insights into molecular biology and microbial evolution.

Map

A vast subset (n=580) of the genomes available for viruses infecting E. coli were downloaded from NCBI on November 16th, 2021. The purpose of this analysis was to visually summarize the patterns of similarity and differences between these organisms on the basis of gene content and total nucleotide identity.

Notes

Based on visual inspection, at least 18 broad groups of viruses can be delineated from the distribution of shared gene content. While some of these viral groups appear to be related to each other, the majority are entirely unique (reflecting their lack of common evolutionary origin). In contrast to bacterial species groups, there is no ‘core’ genome present within this genome collection. Rather, the most interesting features of this map tends to be the small number of similarities (shared genes) which can be found between these diverse groups of viruses.