Known types of viruses in world's oceans tripled

Scientists have tripled the known types of viruses - identifying over 15,000 distinct ones - living in the world's oceans, an advance that may be key to the efforts to protect the planet from global warming.
Greenhouse gases threatening the environment could be mediated by these viruses through manipulation by scientists - something that is at least a couple decades off, but will likely be necessary to manage climate change, researchers said.
The study, led by Ohio State University in the US, will likely have far-reaching implications, including ultimately helping to preserve the environment through reducing excess carbon humans put into the atmosphere.

The oceans currently soak up half of that carbon, but that comes at the cost of acidifying the oceans, which puts some ocean-dwellers, including shellfish, at risk.
Understanding how microbes and viruses interact is critical to any possible management efforts, researchers said.
Their work was possible because of the unprecedented three-year Tara Oceans Expedition, in which a team of more than 200 experts took to the sea to better understand its unseen inhabitants, and the Spanish-led 2010 Malaspina expedition, which evaluated the impact of global change on the ocean and studied its biodiversity.

Researchers processed viral samples collected by scientists aboard the two ships.

Lead author Simon Roux of Ohio State analysed genetic information from those samples to catalogue 15,222 genetically distinct viruses and group them into 867 clusters that share similar properties.
"Ten years ago I would never have dreamt that we could establish such an extensive catalogue of ocean organisms around the world," said Matthew Sullivan, from Ohio State.
"Scientists around the world are revealing how microbes impact our bodies, soil, the air and the oceans. As we improve our ability to study viruses, we're seeing the role viruses play in these microbial functions," Sullivan added.
"These findings have implications far beyond ocean viral diversity and will help us better understand microbial diversity on a global scale," said Melissa Duhaime, an assistant research scientist at University of Michigan.

Roux said microbes in the oceans make half of the oxygen humans breathe, making viruses that infect these microbes particularly important.
"Our work not only provides a relatively complete catalogue of surface ocean viruses, but also reveals new ways that viruses modulate greenhouse gases and energy in the oceans," he said.
At any given time, about one in three cells in the ocean is infected with a virus, altering the way the cell behaves, Roux said.
The team is eager to see how viruses might fit into future efforts to reduce carbon in the atmosphere, researchers said.
The findings were published in the journal Nature.