Variable phosphorus uptake rates and allocation across microbial groups in the oligotrophic Gulf of Mexico

摘要: Microbial uptake of dissolved phosphorus (P) is an important lever in controlling both microbial production and the fate cycling marine P. We investigated relative role heterotrophic bacteria phytoplankton P by measuring rates individual groups (heterotrophic Synechococcus, Prochlorococcus picoeukaryotic phytoplankton) P-depleted Gulf Mexico. Phosphorus were measured using incubations with radiolabelled phosphate adenosine triphosphate coupled cell sorting flow cytometry. found that dominant consumers on a biomass basis population basis. Biovolume normalized rate per (amol μm(-3) h(-1)) was roughly order magnitude greater than rates, responsible for generally 50% total picoplankton uptake. hypothesized this variation reflects cellular allocation strategies, that, indeed, fraction utilized phospholipid significantly higher compared cyanobacterial phytoplankton. These findings indicate have uniquely P-oriented physiology play