Scientists have just discovered and cataloged 15,222 genetically distinct ocean viruses, tripling the number of known marine viruses. Viruses are abundant in the ocean and have effects on most major ecological processes, including carbon cycling. The findings, just published in the journal Nature, will help researchers understand how these microbes impact ecosystems.
Marine viruses are everywhere and affect most metabolic and ecological processes. For example, marine algae are responsible for cycling and using up large amounts of atmospheric carbon, reducing global pollution. However, previous studies have shown that up to one third of marine algae are infected with viruses, which can slow down or even halt these processes. Other marine viruses affect entire ecosystems, food webs, and even evolution. Yet we know very little about these microbes and have only cataloged an estimated 1% or less of viruses found on the surface of the ocean.
Viral samples were collected during the recent Tara Oceans and Malaspina research expeditions. The samples were then analyzed by Ohio State University scientists. The team identified 867 viral clusters (groups of closely related viruses, similar to a genus) that contained a total of 15,222 unique viruses. 75% of the viral clusters were new discoveries and had never been described. The team also found that 38 of the clusters were so abundant that they made up half of the represented viruses in samples.
The team’s findings are massively increasing researchers’ understanding of the diversity and functions of marine viruses. Marine viruses affect most ocean events but have been understudied in the past. Marine microbes are responsible for critical processes such as oxygen production and carbon cycling. This makes it important to study the viruses that may infect these algae and other microbes. Scientists have now tripled the number of known ocean viruses and are continuing to analyze the data from recent expeditions.
Simon Roux et al. Ecogenomics and potential biogeochemical impacts of globally abundant ocean viruses. Nature (2016).