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Updated: May 26, 2026
05:04
Visualization of Productivity Zones Based on Nitrogen Mass Balance Model in Narragansett Bay, Rhode Island
Published on: July 14, 2023
Dynamic model of flexible phytoplankton nutrient uptake
Juan A Bonachela1, Michael Raghib, Simon A Levin
1Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544-1003, USA. jabo@princeton.edu
Summary
Marine microbes exhibit metabolic plasticity, enabling survival in low-nutrient environments. Our dynamic model improves predictions of phytoplankton nutrient uptake and growth rates in the ocean.
Area of Science:
- Marine microbial ecology
- Biogeochemical oceanography
Background:
- Marine microbes display metabolic plasticity, crucial for survival under nutrient limitation.
- Current models often use the Michaelis-Menten (MM) form, which doesn't capture this plasticity.
Purpose of the Study:
- To develop a dynamic cell-level model for marine microbial nutrient uptake.
- To account for the regulation of uptake proteins in response to nutrient availability.
Main Methods:
- Proposed a flexible model where maximum uptake rate and nutrient affinity adjust with external nutrient concentration.
- Modeled protein synthesis regulation based on internal and external nutrient levels.
Main Results:
- The dynamic model predicts higher uptake and growth rates than classic MM for low-to-medium nutrient concentrations.
- Model results align with MM for high nutrient concentrations.
- Demonstrated that maximum uptake rate and nutrient affinity increase as external nutrient concentration decreases.
Conclusions:
- The proposed dynamic model offers a more realistic representation of marine microbial nutrient uptake.
- Current biogeochemical models may underestimate phytoplankton in oligotrophic ocean regions due to the lack of this regulatory mechanism.
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