DocM Posted July 10, 2014 Share Posted July 10, 2014 http://www.simonsfoundation.org/quanta/20140710-hints-of-lifes-start-found-in-a-giant-virus/ Hints of Life?s Start Found in a Giant Virus Chantal Abergel and Jean-Michel Claverie were used to finding strange viruses. The married virologists at Aix-Marseille University had made a career of it. But pithovirus, which they discovered in 2013 in a sample of Siberian dirt that had been frozen for more than 30,000 years, was more bizarre than the pair had ever imagined a virus could be. In the world of microbes, viruses are small ? notoriously small. Pithovirus is not. The largest virus ever discovered, pithovirus is more massive than even some bacteria. Most viruses copy themselves by hijacking their host?s molecular machinery. But pithovirus is much more independent, possessing some replication machinery of its own. Pithovirus?s relatively large number of genes also differentiated it from other viruses, which are often genetically simple ? the smallest have a mere four genes. Pithovirus has around 500 genes, and some are used for complex tasks such as making proteins and repairing and replicating DNA. ?It was so different from what we were taught about viruses,? Abergel said. The stunning find, first revealed in March, isn?t just expanding scientists? notions of what a virus can be. It is reframing the debate over the origins of life. > > Alive or Not? Giant viruses have further blurred the definition of what it means to be alive. According to the standard definition, traditional viruses are not alive because they lack the machinery to replicate their genes and must steal those found in their cellular hosts. But giant viruses seem to lie somewhere between bacterium and virus ? alive and not. They have some genes involved in replication, which indicates that they may have once been free-living organisms that devolved into viruses. Some researchers say that means they deserve their own branch on the tree of life, creating a fourth domain that would leave the other three ? Archaea, bacteria and eukaryotes? largely intact. Also supporting the idea of a giant viral branch is their genetic weirdness: Giant viruses have unusual genes that aren?t found on other branches of the tree. > Link to comment Share on other sites More sharing options...
cacoe Posted July 10, 2014 Share Posted July 10, 2014 Could this also have worked in reverse? Could a bacteria have mutated and formed the virus? +E.Worm Jimmy 1 Share Link to comment Share on other sites More sharing options...
DocM Posted July 11, 2014 Author Share Posted July 11, 2014 That is the big question; which came first, the virus or the bscteria? The jury is still out, and they keep finding increasingly ginormous virii Link to comment Share on other sites More sharing options...
FiB3R Posted July 11, 2014 Share Posted July 11, 2014 "According to the standard definition, traditional viruses are not alive because they lack the machinery to replicate their genes and must steal those found in their cellular hosts." How is it not alive, if it has the ability to steal? Link to comment Share on other sites More sharing options...
DocM Posted July 11, 2014 Author Share Posted July 11, 2014 You can get virus-like behavior by just mixing small strands of RNA in a supportive solution. Some bits join up and parasitically predate in other strands. That doesn't make them "alive." Many virii aren't much more than encapsulated RNA. Lots of debate about alive, or not. These giant virii are another kettle of fish though. Link to comment Share on other sites More sharing options...
+Warwagon MVC Posted July 11, 2014 MVC Share Posted July 11, 2014 The bigger question is, if I don't wash my lettuces before I eat it am I going to die? I always call it immune system boot camp. DarkyDan 1 Share Link to comment Share on other sites More sharing options...
T3X4S Posted July 11, 2014 Share Posted July 11, 2014 Does this mean I should change my underwear more than once a month ? Link to comment Share on other sites More sharing options...
DocM Posted July 11, 2014 Author Share Posted July 11, 2014 At least twice :whistle: T3X4S 1 Share Link to comment Share on other sites More sharing options...
+Warwagon MVC Posted July 11, 2014 MVC Share Posted July 11, 2014 Does this mean I should change my underwear more than once a month ? or until they smell like vinegar Link to comment Share on other sites More sharing options...
cacoe Posted July 11, 2014 Share Posted July 11, 2014 The bigger question is, if I don't wash my lettuces before I eat it am I going to die? I always call it immune system boot camp. Can you become immune to the effects of eating small amounts of pesticide on a regular basis? Link to comment Share on other sites More sharing options...
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