Genome reconstructions indicate the partitioning of ecological functions inside a phytoplankton bloom in the Amundsen Sea Polynya, Antarctica

<p>Phytoplankton blooms are an ecologically important yet not entirely understood phenomenon. This is certainly the case for the massive Phaeocystis blooms in climate-sensitive Antarctic polynyas. They interact with the atmosphere through the exchange of carbon dioxide and dimethylsulfide. They also sustain a distinct bacterial community that might play a role in bloom duration and intensity. Here we deeply sequenced a metagenome from an Amundsen Sea polynya bloom event and determined the genomic content of bacterial populations surrounding Phaeocystis. A pico-eukaryote genome (19.6 Mb) was also recovered. The identification of functional complementarities between P. antarctica and bacterial taxa organized in close association with Phaeocystis colonies makes a contribution to our understanding of bloom functioning in the Southern Ocean.