Project description:The diazotroph Trichodesmium is an important contributor to marine dinitrogen (N2) fixation, supplying so-called new N to phytoplankton in typically N-limited ocean regions. Identifying how iron (Fe) and phosphorus (P) influence Trichodesmium activity and biogeography is an ongoing area of study, where predicting patterns of resource stress is complicated in part by the uncertain bioavailability of organically complexed Fe and P. Here, a comparison of 26 metaproteomes from picked Trichodesmium colonies identified significantly different patterns between three ocean regions: the western tropical South Pacific, the western North Atlantic, and the North Pacific Subtropical Gyre. Trichodesmium metaproteomes across these regions significantly differed in KEGG submodule signals, and vector fitting showed that dissolved Fe, phosphate, and temperature significantly correlated with regional proteome patterns. Populations in the western tropical South Pacific appeared to modulate their proteomes in response to both Fe and P stress, including a comparatively low relative abundance of the N2 fixation marker protein, NifH. Significant increases in the relative abundance of both Fe and P stress marker proteins previously validated in culture studies suggested that Trichodesmium populations in the western North Atlantic and North Pacific were P-stressed and Fe-stressed, respectively. These patterns recapitulate established regional serial and co-limitation patterns of resource stress on phytoplankton communities. Evaluating community stress patterns may therefore predict resource controls on diazotroph biogeography. These data highlight how Trichodesmium modulates its metabolism in the field and provide an opportunity to more accurately constrain controls on Trichodesmium biogeography and N2 fixation.
Project description:RNA-protein dynamics of high CO2-adapted, iron-phosphorus co-limited Trichodesmium reveals nutrient-limited molecular architecture of a globally significant marine nitrogen fixer in a future ocean
Project description:Biogeographic conservation and CO2-dynamics of the cytosine methylome in the globally important cyanobacterium Trichodesmium [RNA-Seq]
Project description:Our paper presents the results of a study in which we used whole genome bisulfite sequencing (WGBS), RNA-Seq (i.e. transcriptomics), high-CO2 physiology experiments, and spatiotemporally separated samples isolated in situ (i.e. directly from the ocean) to examine the metabolic potential of genome-wide cytosine (5mC) methylation (i.e. epigenomics), its potential impacts to transcriptional dynamics under both present-day and future ocean acidification conditions, and its biogeographic conservation in the globally-significant, biogeochemically-critical marine cyanobacterium Trichodesmium.
Project description:This project presents field metaproteomics data from Trichodesmium colonies collected from the surface ocean. Most were collected from the tropical and subtropical Atlantic ocean, but there is also data from the long term Bermuda Atlantic Time Series and Hawaii Ocean Time Series. Trichodesmium is a globally important marine microbe and its growth and nitrogen fixation activity is limited by nutrient availability in the surface ocean. This dataset was generated to answer questions about limitations on Trichodesmium's growth and activity in the nature.
Project description:Our paper presents the results of a study in which we used whole genome bisulfite sequencing (WGBS), RNA-Seq (i.e. transcriptomics), high-CO2 physiology experiments, and spatiotemporally separated samples isolated in situ (i.e. directly from the ocean) to examine the metabolic potential of genome-wide cytosine (5mC) methylation (i.e. epigenomics), its potential impacts to transcriptional dynamics under both present-day and future ocean acidification conditions, and its biogeographic conservation in the globally-significant, biogeochemically-critical marine cyanobacterium Trichodesmium.
Project description:Our paper presents the results of a study in which we used Illumina RNA-Seq (i.e. transcriptomics) and high-CO2 nutrient limitation experiments to examine transcriptional variation of iron-limited, phosphorus-limited, and iron-phosphorus co-limited cultures following long-term (~7 years) low- (380 µatm CO2) and high-CO2 (750 µatm CO2) selection. Hence, we describe the molecular physiology of the globally-significant, biogeochemically-critical marine cyanobacterium Trichodesmium.
