Scientists studying the Megavirus at a laboratory. (Photo: tele13.13.cl)
Giant virus found in the Chilean sea
Wednesday, October 12, 2011, 23:40 (GMT + 9)
Scientists from the Structural & Genomic Information (IGS) laboratory and from the University Aix-Marseille, France, ensure that the virus isolated in the Pacific Ocean off Chile’s coast is the largest known so far in the world.
With 0.7 microns (thousandths of a millimetre) in diameter, the Megavirus chilensis is 10 to 20 times larger than the average virus, which includes the Mimivirus, found in 1992 in a water cooling tower in the United Kingdom.
According to Jean-Michel Claverie and Chantal Abergel, scientists and authors of the study published in the Journal of the Academy of Sciences (PNAS), the Megavirus probably infected amoebas, unicellular organisms that float free in the sea.
"It is larger than some bacteria. An electronic microscope is not necessary to see it as it can be seen with a common light microscope," stated Claverie.
The Megavirus has hair-like structures or fibrils outside the shell, or capsid, which will probably attract the amoebae.
According to a study of DNA, the virus has more than 1,000 genes, the BBC reported.
Furthermore, it was discovered that it had the capacity to build large trojan organelles – cells within cells -- that can produce new viruses to infect other amoebae.
"Everything starts from a single particle and then grows and grows until it becomes a factory of virions (virus particles morphologically complete and infectious). That's why it needs all these genes," said the professor at the University Aix- Marseille.
The Megavirus was found off the coast of Las Cruces, in central Chile, while performing a general biology investigation.
In this regard, Claverie stated that "this is a new way of performing virology."
"Before, only a virus was found out after it had caused a disease in human beings or in animals and plants. But now we are starting what might be called environmental virology and we are looking for viruses everywhere," added the French scientist.
By Analia Murias