No Shortage of New Frontiers

As I start reading (somewhat) recent news about viruses, I get the feeling that I could throw a rock in the dark and hit an article about a new kind of virus that does not meet the definition or current understanding of what a virus is.   The seeming prevalence of these articles reflect two phenomena.   One aspect is, of course, that virology is still a young field because our understanding of viruses quite skimpy compared to their diversity and mysteries.  The other aspect is news reporters prefer to write stories on the new and astounding, and nothing fits this desire better than a story about a weird new virus that’s unlike anything seen before and that blows up the existing paradigms.

An October 2019 news piece at sciencealert.com reported the Japanese discovery of a strange new virus that defies the general agreement that all viruses are genetic material wrapped within a protein container and this particle can infect a cell and replicate itself inside the cell.   This new virus is found in pig feces has no structural proteins, meaning it cannot make a viral particle.  Which poses a giant question: how can the virus exist if it can’t replicate?   Scientists are unsure, but wonder if a helper virus might be part of the answer.  See https://www.sciencealert.com/mysterious-new-virus-could-represent-entirely-new-system-of-viral-evolution and https://doi.org/10.1016/j.meegid.2019.103975

sciencealert.com had a second article in February 2018 about gigantic viruses recently found in Brazil.  These viruses are not just big, they are so big they challenge the notions “what we think a ‘virus’ is.”  Dubbed “Tupanivirus,” these viruses are classified in the Mimiviridae family, and have tailed forms as long as 2.3 micrometer with 1.5 million base pairs of DNA—enough to produce up to 1,425 kinds of proteins.   Interesting, the Japanese pig fece virus lacked proteins entirely, and here in Brazil we have over a thousand proteins.   Not only that, Tupanivirus is capable of doing things that viruses are not supposed to be able to do:  DNA repair, replication, transcription and translation.   See https://www.sciencealert.com/giants-viruses-discovered-brazil-among-largest-most-complex-ever-found-tupanvirus-mimivirus 

~~ Robert Carr