140,000 different viruses have been found in the human intestine, most of which are unknown to science

After the 2020 pandemic, the very word "virus" provokes a poor emotional response, but this phenomenon also has a positive side - hundreds of scientists around the world have switched to this direction. Their efforts have recently created a new catalog of viruses called the "Intestinal Phage Database". It contains 142, 809 hitherto unknown viruses from the category of bacteriophages that live in the human intestine, and the purpose of which raises many questions.

It should be noted right away that we are not talking about another global threat, but about the normal situation in the intestines of a healthy person. Biomaterial donors were specially selected from among non-sick people from 28 countries, 28, 000 individual metagenomes of viruses were collected, plus 2, 900 genomes of intestinal bacteria. All of them are an integral part of the human gut ecosystem, but in light of new discoveries, scientists had to rethink the roles of these microorganisms.

The previous simplified scheme, according to which bacteria were responsible for the functions of digestion, and bacteriophages eliminated threats from the outside, is categorically outdated. So, at least a third of viruses were able to infect different types of bacteria and, in the process, transfer gene flows between them. Bacteriophages have become at the center of the dynamic process of coevolutionary interaction; they serve both to cull unusable bacteria and to transfer useful functions to others through genetic transfer. But this is mostly speculation, large-scale work with a new database of intestinal phages is only gaining momentum.