Dataset Information

Dynamic model of flexible phytoplankton nutrient uptake.

ABSTRACT: The metabolic machinery of marine microbes can be remarkably plastic, allowing organisms to persist under extreme nutrient limitation. With some exceptions, most theoretical approaches to nutrient uptake in phytoplankton are largely dominated by the classic Michaelis-Menten (MM) uptake functional form, whose constant parameters cannot account for the observed plasticity in the uptake apparatus. Following seminal ideas by earlier researchers, we propose a simple cell-level model based on a dynamic view of the uptake process whereby the cell can regulate the synthesis of uptake proteins in response to changes in both internal and external nutrient concentrations. In our flexible approach, the maximum uptake rate and nutrient affinity increase monotonically as the external nutrient concentration decreases. For low to medium nutrient availability, our model predicts uptake and growth rates larger than the classic MM counterparts, while matching the classic MM results for large nutrient concentrations. These results have important consequences for global coupled models of ocean circulation and biogeochemistry, which lack this regulatory mechanism and are thus likely to underestimate phytoplankton abundances and growth rates in oligotrophic regions of the ocean.

SUBMITTER: Bonachela JA

PROVIDER: S-EPMC3251133 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Dynamic model of flexible phytoplankton nutrient uptake.

Bonachela Juan A JA Raghib Michael M Levin Simon A SA

Proceedings of the National Academy of Sciences of the United States of America 20111205 51

The metabolic machinery of marine microbes can be remarkably plastic, allowing organisms to persist under extreme nutrient limitation. With some exceptions, most theoretical approaches to nutrient uptake in phytoplankton are largely dominated by the classic Michaelis-Menten (MM) uptake functional form, whose constant parameters cannot account for the observed plasticity in the uptake apparatus. Following seminal ideas by earlier researchers, we propose a simple cell-level model based on a dynami ...[more]

PMID: 22143781

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Dataset Information

Dynamic model of flexible phytoplankton nutrient uptake.

Publications

Dynamic model of flexible phytoplankton nutrient uptake.

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