Mega beats Mimi for world's biggest virus
Giant virus discovered in Chile 'doesn't seem to be harmful for humans.'
Mon, Oct 10, 2011 at 03:06 PM
FORMER VIRAL CHAMP: Images of defibered Mimiviruses. The Mimivirus was isolated in 2003. The recently discovered Megavirus chilensis is 6.5 percent bigger. (Images: Wikimedia Commons)
PARIS — A virus found in the sea off Chile is the biggest in the world, harboring more than 1,000 genes, surprised scientists reported on Oct. 10.
The genome of Megavirus chilensis is 6.5 percent bigger than the DNA code of the previous virus record-holder, Mimivirus, isolated in 2003.
Viruses differ from bacteria in that they are usually far smaller and cannot reproduce on their own, needing to penetrate a host cell in which to replicate.
But M. chilensis is such a giant that it surpasses many bacteria in size and is genetically the most complex DNA virus ever described.
It was taken from sea water sample closed to the shore of Las Cruces, Chile. Its host organism is unknown.
DNA viruses include pox viruses and herpes viruses, but M. chilensis "doesn't seem to be harmful for humans," said Jean-Michel Claverie, of France's National Centre for Scientific Research (CNRS).
The study appears in a U.S. journal, Proceedings of the National Academy of Sciences (PNAS).
Copyright 2011 AFP Global Edition