MEP Darwin Project

Collaborative Research: Predicting the Spatiotemporal Distribution of Metabolic Function in the Global Ocean

NSF Bio OCE Collaborative Grant Awards #1558710 and #1558702

Prinicple Investigators:
    Joe Vallino (MBL)
    Mick Follows (MIT)

Postdoctoral Investigator:
    Aboozar Tabatabai

Data Management:
    BCO-DMO

This project builds upon the Darwin Project, a trait and selection based modeling approach for describing marine plankton communities and biogeochemical cycles. The approach relies on local competition to select from a diverse population and determines the functional characteristics of microorganisms that mediate biogeochemical cycles. The project will combine this selection-based modeling approach with a distributed metabolic network perspective previously developed to facilitate calculating reaction thermodynamics. This will provide mechanistic and quantitative description of key metabolic functions and allow the new model to be directly mappable to omics-based observations. The project will utilize new modeling design criteria based on the maximum entropy production (MEP) conjecture to determine allocation of metabolic machinery and its expression, such as metabolic switching between nitrogen fixation and ammonium uptake. Model testing will rely on existing oceanographic surveys and observations. Once validated, the coupled model will be used to investigate losses of functional biodiversity, generalist versus specialists, temporal planktonic strategies as well as losses in community complementarity on ecosystem biogeochemistry. A significant output from the project will be a predicted global biogeography map of metabolic function and expression (such as nitrogen fixation and ammonium oxidation) that can be tested with, and used to interpret, directed omics observations.