Marine Dissolved Metabolite Concentrations Provide Unique Insights into Microbial Metabolic Processes over Diurnal and Seasonal Time-Scales

Microorganisms drive the marine carbon cycle by controlling the rates of carbon fixation and remineralization in ocean environments. Embedded within the bulk rates of this cycle are metabolic reactions catalyzed by enzymes expressed by microbes in response to changing nutrient concentrations, light levels and temperature. Metabolite dynamics, thus, integrate a microbe’s response to external parameters and metabolite concentrations and/or fluxes can be used to infer relative importance of different biogeochemical processes within the carbon cycle. Repeated and sustained observations of dissolved metabolites are still rare but can provide complementary insights to those gained from genomics and other systems biology tools. This presentation will summarize three years of bi-monthly dissolved metabolite analyses in the upper 1000m of the Bermuda Atlantic Time Series (BATS) site in the Atlantic Ocean. Within our metabolite measurements, we see evidence of short-lived molecules, indicative of extensive metabolite recycling in biologically-active regions in the water column. We further observe the overturning imprint on deepening metabolite concentrations in the winter and elevated metabolite concentrations during the spring bloom in the surface. These data will be integrated with complementary laboratory culture results, environmental meta-data and in situ biological measurements to develop novel hypotheses about the mechanisms within the marine carbon cycle at BATS. Our approach could be extended to basin-scale or process-oriented field studies to integrate with anticipated BioGeoSCAPES partners.