The Cosmopolitan Gut Virus crAssphage


  • Linda Smith PhD student



Bioinformatics, Microbiology


CrAss-like phages are a diverse group of mostly uncultured bacterial viruses that are highly abundant in the mammalian gut and other habitats. First identified in metagenomic sequences from human faeces in 2014, crAss-like phages were predicted to infect members of the phylum Bacteroidetes. Later work resulted in the isolation of the first cultured representatives, the confirmation of a Podoviridae-like morphology and a proposal to classify uncultured crAss-like phages under a novel taxonomic group. The International Committee on Taxonomy of Viruses (ICTV) has recently acknowledged the creations of a new order Crassvirales, comprising at the moment four new families, ten new subfamilies, 42 new genera and a total of 73 new species. Many unanswered questions remain about this ubiquitous yet enigmatic gut virus which I aim to approach in my research through computational analysis of metagenomic sequences.


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