It suggests the presence of a virus similar to organisms that prey on and take over cells
Viruses are said to be "non-living" because of their characteristics such as "no cells" and "no self-propagation". However, the virus is evolving every day due to the competition for survival, and the definition of the virus is fluctuating due to the discovery of a new virus with characteristics similar to those of living organisms.
Clades of huge phages from across Earth ’s ecosystems | Nature
Huge bacteria-eating viruses close gap between life and non-life: Large bacteriophages carry bacterial genes, including CRISPR and ribosomal proteins-ScienceDaily
A type of virus that infects bacteriaBacteriophageHas a distinctive shape type that is divided into a head and a tail.
The University of California research team has a large database of DNA from more than 30 different environments, from the natural environment, such as the sea and underground, to the intestines of premature babies and pregnant women. The researchers have identified as many as 351 giant bacteriophages, more than four times the average virus genome. There is also a bacteriophage with a genome of 735,000 base pairs, which is about 15 times the average, and this is said to be the largest bacteriophage at the time of writing the article.
Giant bacteriophage genes are the structures by which cells synthesize proteins.RibosomeIt has been revealed that it has a gene for a protein that is indispensable for. "The presence or absence of ribosomes is one of the criteria for separating living and non-living organisms. The fact that non-living viruses have genes essential for ribosomes means that living organisms have genes essential for ribosomes," said researcher Rohan Sachdeva, co-author of the paper. Blurs the line between non-living things. "
It has been suggested that bacteriophage ribosome genes may be capable of manipulating ribosomes in the cells of the host bacteria to make more copies of the bacteriophage protein.
"It is thought that giant bacteriophages were born out of a survival strategy. What we defined as a virus," said Jill Banfield, professor of environmental science at the University of California and lead author of the paper. It can be considered a hybrid of living things. " Banfield announced in 2019the studyReports that some of the giant bacteriophages called Lak phages are present in the human intestine and mouth and prey on the intestinal and salivary microflora.
In addition, the DNA of the large bacteriophage contains bacteria that can resist the virus.CRISPRPart of the system is included. It is thought that bacteriophage can inject DNA into the host bacterium, hijacking the host's CRISPR system and targeting only non-bacteriophage viruses.
Although it has not been specified what the effects of a large bacteriophage on humans, Banfield said, "Human illness can be caused indirectly by bacteriophages. And the ability to move around genes associated with resistance to antibiotics and antibiotics, and the larger the genome, the easier it is to move around the genes, so the higher the probability of carrying unnecessary genes to human bacteria. '' Talking.