Dynamic model of flexible phytoplankton nutrient uptake

Juan A. Bonachela, Michael Raghib, Simon Asher Levin

Research output: Contribution to journalArticle

72 Scopus citations

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.

Original languageEnglish (US)
Pages (from-to)20633-20638
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume108
Issue number51
DOIs
StatePublished - Dec 20 2011

All Science Journal Classification (ASJC) codes

  • General

Keywords

  • Acclimation
  • Nutrient-uptake kinetics
  • Phenotypic plasticity
  • Uptake sites

Fingerprint Dive into the research topics of 'Dynamic model of flexible phytoplankton nutrient uptake'. Together they form a unique fingerprint.

  • Cite this