Revelation in the gut virome

Abstract

Virology Some of the trillions of bacteria in the human gut are beginning to disclose their secrets. By contrast, we know little about the viruses other than that there are even more of them and most parasitize bacteria and other microbiota. Guerin et al. systematically investigated fecal DNA bacteriophages called crAssphages, which appear to infect Bacteroidetes. These phages are found in about half of individuals, constitute 90% of fecal DNA, and show differences in health and disease (for example, in malnourished infants). crAssphage genes tend not to match known sequences, but, through the use of a variety of methods on almost 100 complete circular genomes extracted from more than 700 human gut microbiota, four crAssphage subfamilies were found, each composed of 10 genera and with short-tailed icosahedral podovirus structures. Cell Host Microbe 24 , 653 (2018).