Virom - the so-called viral and bacteriological environment of the body, unique for every person, according to the Internet edition for girls and women from 14 to 35 years Pannochka. net Once in the body, the bacteria undergo rapid changes in it; on the basis of a unique environment, each person has his own resistance to disease and susceptibility to drugs.
People are not just the sum of cells that form tissues and organs. The digestive tract, for example, is home to huge colonies of bacteria of all sorts, as well as many viruses that prey on these bacteria.
Since the types of bacteria within organisms of different people differ, viral populations, whose composition is called virome (virome).
By tracking and analyzing a person's viro for more than two years, researchers from the Perelman School of Medicine at the University of Pennsylvania, led by Professor of Microbiology Frederick D. Bushman (Frederic D. Bushman) made important conclusions about the ways in which the viral population is, and why the virions of different people can radically differ. The evolution and diversity of viromas can affect susceptibility and resistance to disease. The work was published in Proceedings of the National Academy of Sciences.
Most of the viroma consists of bacteriophages, viruses that do not damage the cells of the human body, and the bacteria in it. Yet the changes that bacteriophages carry to bacteria are reflected in humans. "Bacterial viruses are predator-hunting bacteria, reducing their numbers," Bushman says.. "Bacterial viruses also transport toxins genes, virulence factors that change the phenotype of their bacterial host". Thus, innocent, benign bacteria living within the body can be turned into dangerous threats by viruses.
16 times in 884 days, researchers collected stool samples of healthy men and extracted virus particles using several methods. They then isolated and analyzed the DNA of adjacent sequences using ultra-deep genome sequencing.
"We collected the raw sequence data for obtaining complete and partial genomes and analyzed how they changed in more than two years of observations". The result was the longest, most extensive picture of the work of the human virom, received so far. Physicians found that although about 80% of known virus types basically remained unchanged throughout the study, certain types of viruses changed very significantly. "We can even justifiably assert that we have observed the formation of new species".
This was particularly noticeable in the Microviridae group: they are bacteriophages with single-stranded DNA ring genomes. A number of genetic mechanisms have encouraged changes, including the replacement of basic chemicals; generating a variety of retroelements in which reverse enzyme transcriptase induces genome mutations; and CRISPRs (Clustered Regularly Interspaced Short Palindromic Repeats, which means "grouped and regularly interrupted inserts of short palindromic repeats") in which parts of the DNA sequence of bacteriophages are included as spacers in bacterial genomes.
This rapid development of the virom was the most unexpected discovery. Bushman notes that "different people have completely different bacteria in the intestines, so they also had viral predators. Another reason why people's viromas differ is that some viruses that get inside a person change very quickly.
Thus, some viral communities diversify and become unique in the body of each person ".
Since people acquire bacterial populations and accompanying viromas after birth, from food and numerous environmental factors, it is logical that the microbial population living in each of us will differ. But this work, say the researchers, shows that no less important factor is the very rapid evolution of the viro in the body.
This fact is of great importance for how the susceptibility and resistance to disease can differ in different people, as well as the effectiveness of drugs for each individual person.
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