@article {Thompson2012, title = {Unicellular cyanobacterium symbiotic with a single-celled eukaryotic alga}, journal = {Science}, volume = {337}, number = {6101}, year = {2012}, note = {tex.mendeley-tags: 2012,microb3,rcc,sbr?hyto$_\textrmd$ipo}, pages = {1546{\textendash}1550}, abstract = {Symbioses between nitrogen (N)2{\textendash}fixing prokaryotes and photosynthetic eukaryotes are important for nitrogen acquisition in N-limited environments. Recently, a widely distributed planktonic uncultured nitrogen-fixing cyanobacterium (UCYN-A) was found to have unprecedented genome reduction, including the lack of oxygen-evolving photosystem II and the tricarboxylic acid cycle, which suggested partnership in a symbiosis. We showed that UCYN-A has a symbiotic association with a unicellular prymnesiophyte, closely related to calcifying taxa present in the fossil record. The partnership is mutualistic, because the prymnesiophyte receives fixed N in exchange for transferring fixed carbon to UCYN-A. This unusual partnership between a cyanobacterium and a unicellular alga is a model for symbiosis and is analogous to plastid and organismal evolution, and if calcifying, may have important implications for past and present oceanic N2 fixation.}, keywords = {2012, MicroB3, rcc, SBR$_\textrmP$hyto$_\textrmD$PO, sbr?hyto$_\textrmd$ipo}, doi = {10.1126/science.1222700}, url = {http://www.sciencemag.org/content/337/6101/1546.abstract}, author = {Thompson, Anne W and Foster, Rachel A and Krupke, Andreas and Carter, Brandon J and Musat, Niculina and Vaulot, Daniel and Kuypers, Marcel M M and Zehr, Jonathan P} }