Project description:Demosponge Cinachyrella cf cavernosa is an inter-tidal sponge. It is found in competition with soft coral Zoanthus sansibaricus and macroalgae Dictyota ciliatum. The effect of these two spatial competitors on the gene expression profile of the sponge is checked. Sponges are collected from three distinct situations, 1. sponge without competitors, 2. sponge in competition with algae, and 3. sponge in competition with soft coral. Each group has three biological replicates.
Project description:Measure changes in dissolved organic matter composition and resulting microbial decomposition rates in an experimentally warmed peatland.
Project description:Sponges are efficient filter feeders, removing significant portions of particulate and dissolved organic matter (POM, DOM) from the water column. While the assimilation and respiration of POM and DOM by sponges and their abundant microbial symbiont communities have received much attention, there is virtually no information on the impact of sponge holobiont metabolism on the composition of DOM at a molecular-level. We applied untargeted and targeted metabolomics techniques to characterize DOM in seawater samples prior to entering the sponge (inhalant reef water), in samples exiting the sponge (exhalent seawater), and in samples collected just outside the reef area (off reef seawater). Samples were collected from two sponge species, Ircinia campana and Spheciospongia vesparium, on a near-shore hard bottom reef in the Florida Keys. Metabolic profiles generated from untargeted metabolomics analysis indicated that many more compounds were enhanced in the exhalent samples than in the inhalant samples. Targeted metabolomics analysis revealed differences in diversity and concentration of metabolites between exhalent and off reef seawater. For example, most of the nucleosides were enriched in the exhalent seawater, while the aromatic amino acids, caffeine and the nucleoside xanthosine were elevated in the off reef water samples. Although the metabolic profile of the exhalent seawater was unique, the impact of sponge metabolism on the overall reef DOM profile was spatially limited in our study. There were also no significant differences in the metabolic profiles of exhalent water between the two sponge species, potentially indicating that there is a characteristic DOM profile in the exhalent seawater of Caribbean sponges. Additional work is needed to determine whether the impact of sponge DOM is greater in habitats with higher sponge cover and diversity. This work provides the first insight into the molecular-level impact of sponge holobiont metabolism on reef DOM and establishes a foundation for future experimental studies addressing the influence of sponge-derived DOM on chemical and ecological processes in coral reef ecosystems.
2016-02-01 | MTBLS281 | MetaboLights
Project description:Heterotroph response to phytoplankton dissolved organic matter
Project description:Direct injection mass spectrometry data for publication titled: "Drought reduces release of plant matter into dissolved organic matter potentially restraining ecosystem recovery"
