Does the key to unravelling the origin of viruses lie in Antarctica ? Image Credit: CC BY-SA 2.0 Liam Quinn
The microorganism was discovered in the lakes of the Rauer Islands off the coast of Antarctica.
Compared to other life forms, viruses are actually quite unusual. Instead of being comprised of cells, most viruses consist of little more than a piece of genetic material encased inside a protective shell.
When a virus enters a living cell, it begins to replicate itself, often to the detriment of the host.
Exactly where viruses first originated however has long remained a topic of debate among scientists. Are they an ancient, simpler form of life, or did they evolve later when cells first began to appear ?
Now a team of scientists from the University of New South Wales in Australia have found a unique type of microorganism in Antarctica that they believe might hold the answer.
Known as Halorubrum lacusprofundi R1S1, the peculiar find is a type of single-celled organism called an archaean which, despite resembling a bacterium, is actually something very different.
When they analyzed this microorganism, the scientists discovered a small fragment of DNA known as a plasmid. To their surprise, this particular plasmid (pR1SE) behaved much the same way as a virus does, suggesting that it could in fact be the form of life from which viruses originally developed.
The find seems to align with what is known as the "escape hypothesis" of virus origination, which suggests that genes 'escaped' from cells and became viruses.
"Traditionally the escape hypothesis has been associated with the idea that viruses are recent," said biologist Patrick Forterre. "Now the escape hypothesis should be viewed in a broader context."
Source: New Scientist | Comments (3)