Award: OCE-1059884

Phytoplankton are tiny organisms that live in the ocean and conduct photosynthesis. They are sometimes referred to as the "plants of the sea" because they use photosynthesis to consume carbon dioxide in the same way that plants do on land. Healthy phytoplankton take up a lot of carbon dioxide, and thereby act to draw carbon dioxide from the atmosphere into the ocean. Since carbon dioxide levels in the atmosphere are increasing due to the burning of fossil fuels, it is important that scientists understand what makes phytoplankton healthy and unhealthy. One way that phytoplankton can become unhealthy is by becoming infected with viruses, just like people can catch the flu. In fact, the viruses that infect phytoplankton are not so different from the flu viruses that infect humans. Viral infection of phytoplankton is a natural process that has gone on for millions of years, but scientists don't really understand how exactly phytoplankton become infected by viruses, what kind of oceanographic conditions encourage infection, or where in the ocean infection occurs. Our research explored these mysteries in laboratory experiments and in the North Atlantic Ocean. We uncovered how a group of molecules, called glycosphingolipids, are involved in viral infection. We also learned about the different types of viruses by analyzing DNA in the ocean. It turns out that it is easier, faster, and more accurate to measure glycosphingolipids and viral DNA than to look for phytoplankton viruses in seawater under a microscope, and we produced the first maps of viral infection in the ocean. Critically we were able to understand what kind of oceanographic conditions make phytoplankton unhealthy, and showed that viruses impact the ability of phytoplankton to do photosynthesis and contribute to drawing carbon dioxide from the atmosphere into the ocean. Last Modified: 07/09/2014 Submitted by: Benjamin Van Mooy