Mollivirus sibericum, the new giant virus – Le Figaro

Found in the permafrost of Siberia and then reactivated by the laboratory genomic and structural information (CNRS / Aix-Marseille University), he is old than 30,000 years.

Mollivirus sibericum is the fourth giant virus discovered in the world. “This is probably the first truly resurrected virus after 30,000 years and which no longer exists on Earth, told Science et Avenir Jean-Michel Claverie, laboratory director and structural genomics information (CNRS / Aix-Marseille ). This is the difference with the pithovirus reactivated last year because we know that there are still today pithovirus. “

Observable by light microscopy

These are called predecessors Megavirus, discovered in 2003, pandoravirus, discovered in 2013 in the waters off Chile and pithovirus, also found in Siberian permafrost in 2014. The four are observable with a conventional microscope and have a high number of genes encoding over 500 proteins.

But here the similarity stops. In fact, these four viruses have in common that their size. “It’s like watching cars of different brands and having the same color and they decided that they form a family on that one criterion of color,” says Jean-Michel Claverie.

Mollivirus has the shape of an elongate shell of about 0.6 microns in length containing a genome of approximately 650,000 base pairs coding for over 500 proteins. These proteins have not the slightest resemblance to those produced by pithovirus, mimivirus or pandoravirus. The Mollivirus is very dependent on its host because it uses the cell nucleus to replicate in amoeba, which brings the small viruses. Other giant viruses identified so far have at least a portion of the machinery required for protein production and replication.

This discovery shows that very different types of virus were able to survive on very long periods in the permafrost, which potentially pathogenic species. “Of course, as soon as it detects a new virus, we ensure firstly the absence of disease risks to humans’ reassures Jean-Michel Claverie.

The consequences of global warming

But the concern is fueled by global warming that melts the permafrost and colonization by desert man today as part of oil and mining exploration. “Global warming also makes places (once) completely inaccessible accessible, Jean Michel Claverie worries in an interview with France Info. Layers that have not been disturbed for millions of years going back to the surface. “

So far no humans in these areas made it impossible contamination. The arrival of man in these areas hitherto desert could create a real danger of contamination by viruses buried in ice for tens or even hundreds of thousands of years. An already largely anticipated by the cinema scenario.