11 October 2011

Mongo the Megavirus

According to the BBC scientists have discovered the largest ever virus in ocean water pulled up off the coast of Chile.

Called Megavirus chilensis, it is 10 to 20 times wider than the average virus.
It just beats the previous record holder, Mimivirus, which was found in a water cooling tower in the UK in 1992.  The particle measures about 0.7 micrometres (thousandths of a millimetre) in diameter... which believe me, is big by virus standards!

"It is bigger than some bacteria," explained Prof Jean-Michel Claverie, from Aix-Marseille University, Marseille, France. "You don't need an electron microscope to see it; you can see it with an ordinary light microscope,"

Viruses cannot copy themselves; they need to invade a host cell if they want to replicate. Like Mimivirus, Megavirus has hair-like structures, or fibrils, on the exterior of its shell, or capsid, that probably attract unsuspecting amoebas looking to prey on bacteria displaying similar features.

A study of the giant virus's DNA shows it to have more than a thousand genes, the biochemical instructions it uses to build the systems it requires to replicate once inside its host.

Megavirus was found off the coast of Las Cruces, central Chile. It was recovered as part of a general trawl in the ocean for biology of interest.
"Previously, we only discovered viruses because they caused disease in
humans, or animals and plants," said Prof Claverie "But now we are initiating what might be called environmental virology and we are looking for viruses everywhere. You just go to lakes, seas and oceans and pick up the water, and then you filter it, and try to rescue the virus by co-cultivating it with some potential host."

Prof Claverie said the megavirus would not be hazardous to humans.

I like the idea of humungous viruses... well humungous by virus standards anyway. I daresay a much larger cousin will be found in due course


susan said...

Of course, if the ocean catches a cold from one of the the consequences could be moisture for all.

jams o donnell said...

Haha Susan!