It appears that the newly discovered virus lacks the proteins required for replication itself. But it somehow thrives, according to a new study.
To discover this mysterious virus, a group of researchers in Japan spent nearly a decade analyzing pig and cow pop for new viruses. These filthy environments, where many animals are constantly interacting, are a good place for the rapid development of viruses, according to a statement from Tokyo University of Agriculture and Technology in Japan.
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Researchers have discovered several new viruses on farms that have been recombined ̵
Mysteriously, the newly discovered microbe has no function present in all other known viruses – the so-called "structural proteins" that help the parasite bind and enter host cells, then replicate. Although the new enterovirus lacks the genes that encode these structural proteins, it has several "unknown" genes, according to researchers.
"That's very strange," senior author Tetsuya Mizutani, director of the Global Infectious Disease Prevention and Education (TUAT) study and education center in Japan, told Live Science in an email.
Without structural proteins, the virus should not be able to infect other cells, he added.
However, three years later, the researchers found the same virus in pork bones on the same farm, suggesting the virus was a recurrence in pigs. Scientists have analyzed the lot they collected from other farms and also found this virus available.
So how does the virus that they named the type 2 EV-G survive? Mizutani and his team hypothesize that the virus borrows structural proteins from other nearby viruses called "helper viruses".
This is not entirely unheard of. The hepatitis D virus needs the hepatitis B virus to reproduce in the body, even though it has its own structural proteins, said Dr. Ames Adalla, infectious disease specialist and senior scientist at the Johns Hopkins Health Center in Baltimore, which I was not involved in the study.
"Understanding how viral recombination occurs and how viruses develop addiction to assisted viruses is an important key to unlocking some of the mysteries of virus evolution," Adalja told Live Science.
There are currently over 30 virus families in the world. which may have evolved from one or more common ancestors, Mizutani said. It is clear that not all have evolved from random mutations in their genomes but are combined with each other, just like the ancestors of a Type 2 EV-G, he added. Now Mizutani and his team are hoping to figure out which helper viruses allow 2 EV-Gs to survive and what exactly the unknown genes do.
The results were published July 22 in the journal Infection, Genetics and Evolution. .
Originally published by Live Science .