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View Full Version : Giant virus resurrected from 30,000-year-old ice



MfA
03-04-2014, 09:32 PM
The discovery of an infectious giant virus that had been entombed in Siberian permafrost for 30,000 years has led scientists to warn of other disease-causing viruses and microbes that may escape from the frozen earth once it has melted.

Scientists in France and Russia discovered the giant virus in samples of frozen earth taken from the far north-east of Russia. Tests in the laboratory showed that the virus was capable of infecting amoeba – single-celled micro-organisms – although it cannot infect multi-cellular animals and humans.



Abstract

The largest known DNA viruses infect Acanthamoeba and belong to two markedly different families. The Megaviridae exhibit pseudo-icosahedral virions up to 0.7 μm in diameter and adenine–thymine (AT)-rich genomes of up to 1.25 Mb encoding a thousand proteins. Like their Mimivirus prototype discovered 10 y ago, they entirely replicate within cytoplasmic virion factories. In contrast, the recently discovered Pandoraviruses exhibit larger amphora-shaped virions 1 μm in length and guanine–cytosine-rich genomes up to 2.8 Mb long encoding up to 2,500 proteins. Their replication involves the host nucleus. Whereas the Megaviridae share some general features with the previously described icosahedral large DNA viruses, the Pandoraviruses appear unrelated to them. Here we report the discovery of a third type of giant virus combining an even larger pandoravirus-like particle 1.5 μm in length with a surprisingly smaller 600 kb AT-rich genome, a gene content more similar to Iridoviruses and Marseillevirus, and a fully cytoplasmic replication reminiscent of the Megaviridae. This suggests that pandoravirus-like particles may be associated with a variety of virus families more diverse than previously envisioned. This giant virus, named Pithovirus sibericum, was isolated from a >30,000-y-old radiocarbon-dated sample when we initiated a survey of the virome of Siberian permafrost. The revival of such an ancestral amoeba-infecting virus used as a safe indicator of the possible presence of pathogenic DNA viruses, suggests that the thawing of permafrost either from global warming or industrial exploitation of circumpolar regions might not be exempt from future threats to human or animal health.


http://www.pnas.org/content/early/2014/02/26/1320670111

http://www.nature.com/news/giant-virus-resurrected-from-30-000-year-old-ice-1.14801

MikeWhalen
03-04-2014, 10:49 PM
I am probably being a dopey scared-y cat, but it is this exact kind of thing that scares the crap out of me and I wish they would not mess with such things...some scientist playing with it, tweeking it and all of a sudden, you get a real 'Walking Dead' scenario!

M

Anglecynn
03-04-2014, 11:58 PM
I am probably being a dopey scared-y cat, but it is this exact kind of thing that scares the crap out of me and I wish they would not mess with such things...some scientist playing with it, tweeking it and all of a sudden, you get a real 'Walking Dead' scenario!

M

It's waiting for a movie. In fact probably already has been.

You can imagine, permafrost melting, flooding, disease spreads, global pandemic.

Well we are due one, let's just hope it's this lot that come back to life, and not dangerous ones. :P