More than 5,000 new types of viruses have been identified in the world’s oceans, according to a new study.
Study researchers analyzed tens of thousands of water samples from around the world, looking for RNA viruses or viruses using RNA as hereditary material. The new coronavirus, for example, is a type of RNA virus. These viruses are studied in comparison with DNA viruses which use DNA As genetic material, the authors said.
The diversity of newly discovered viruses was so great that researchers suggested doubling the number of taxonomic groups needed to classify RNA viruses from the current 5 to 10 phyla. (Era is a broad classification in biology that falls under the “domain”.)
“There are a lot of new varieties here – and a complete diversity [new] One phylum, Taraviricota, is found in all oceans, indicating that it is ecologically important,” said lead author Matthew Sullivan, professor of microbiology at Ohio State University. He said in a statement (Opens in a new tab).
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According to Sullivan, studies of RNA viruses generally focus on those that cause disease. (Some well-known RNA viruses include influenza, Ebola, and the coronavirus that causes COVID-19.) But that’s just a “small slice” of RNA viruses on Earth, Sullivan said.
“We wanted to study it systematically on a large scale and explore an environment that no one had analyzed in depth,” Sullivan said in the release.
For the study published Thursday, April 7 in the journal Science (Opens in a new tab)In the study, researchers analyzed 35,000 water samples taken from 121 locations in the world’s five oceans. The researchers are part of the Tara Ocean Consortium, a global project to study the impact of Climate change in the ocean.
The researchers said they examined genetic sequences extracted from small aquatic organisms known as plankton, which are common hosts for RNA viruses. They established sequences belonging to RNA viruses by searching for an ancient gene called RdRp, which is found in all RNA viruses but is absent from other viruses and cells. They identified more than 44,000 sequences with this gene.
But the RdRp gene is billions of years old and has evolved many times. Since the evolution of the gene is very old, it has been difficult for researchers to determine the evolutionary relationship between the sequences. So the researchers used machine learning to organize them.
Overall, they identified about 5,500 new species of RNA viruses belonging to the five existing classes, in addition to the five newly proposed classes, which the researchers called Taraviricota, Pomiviricota, Paraxenoviricota, Wamoviricota and Arctiviricota.
Virus species from the phylum Taraviricota were particularly abundant in temperate and tropical waters, while viruses from the phylum Arctiviricota are abundant in the Arctic Ocean, the researchers write in Conversation. (Opens in a new tab)
Understanding how the RdRp gene varies over time can lead to a better understanding of early childhood development. EarthThe authors said.
“RdRp is probably one of the oldest genes – it was present before DNA was needed,” said study co-author Ahmed Zayed, a microbiology researcher at Ohio State, in the press release. Thus, we trace not only the origin of viruses, but also the origins of life.
Originally posted on Live Science.