Scientists discover nearly 100,000 new types of viruses

A groundbreaking study from Tel Aviv University has discovered around 100,000 new types of viruses previously unknown – a nine-fold increase in the number of RNA viruses known to science so far. These viruses have been discovered in global environmental data from soil samples, oceans, lakes and other ecosystems. This discovery could contribute to the development of antimicrobial drugs and protect against fungi and parasites harmful to agriculture.

To study: Global RNA virome expansion reveals diverse bacteriophage clades. Image Credit: Golden Wind / Shutterstock

Doctoral student Uri Neri led the study under the supervision of Professor Uri Gophna of the Shmunis School of Biomedicine and Cancer Research at the Wise School of Life Sciences at Tel Aviv University. The research was carried out in collaboration with the American research organizations NIH and JGI, as well as with the Institut Pasteur in France. The study was published in the prestigious log Cell and included data collected by more than a hundred scientists from around the world.

Viruses are genetic parasites, which means that they must infect a living cell to reproduce their genetic information, produce new viruses and complete their cycle of infection. Some viruses are pathogens that can harm humans (like the coronavirus). Yet the vast majority of viruses do not harm us and infect bacterial cells – some even live inside our bodies without our being aware of them.

Uri Neri says the study used new computer technologies to extract genetic information from thousands of different sampling points around the world (oceans, soil, sewage, geysers, etc.). The researchers developed a sophisticated computer tool that distinguishes between the genetic material of RNA viruses and that of hosts and used it to analyze big data. The discovery allowed researchers to piece together how viruses underwent various acclimation processes throughout their evolutionary development to adapt to different hosts.

By analyzing their findings, the researchers identified viruses suspected of infecting various pathogenic microorganisms, opening up the possibility of using viruses to control them.

“The system we have developed allows for in-depth evolutionary analyzes and understanding of how different RNA viruses developed over evolutionary history. One of the key questions in microbiology is how and why viruses transfer genes between themselves We have identified a number of cases in which such gene exchanges have allowed viruses to infect new organisms. RNA in microbial ecosystems are not well understood In our study, we found that RNA viruses are not unusual in the evolutionary landscape and, in fact, in some respects they are not so different from viruses This opens the door for future research and a better understanding of how viruses can be harnessed for use in medicine and agriculture,” said Professor Gophna

Overall, the results show a great expansion in the diversity of orthornavirus, in particular that of RNA viruses associated with bacteria. Additionally, they introduce relatively minor changes to the latest taxonomic scheme, supporting its overall robustness. Moreover, RNA viruses are believed to have multiple protein functions. This work has generated a large number of sequences and derivatives, accessible through the companion website (riboviria.org) or through the Zenodo repository. By using this resource, researchers can gain meaningful context when describing new RNA viruses in future research. For example, by obtaining information about the ecological distributions of specific viral lineages or by annotating their specific protein domains. Additionally, this resource can help researchers identify key RNA virus genomes that can be further characterized experimentally.