Mathematically modeling stoichiometric drivers of heterotrophic N2 fixation
The major source of nitrogen (N) to the biosphere is biological N2 fixationthe microbially-mediated reduction of abundant but inert N2 gas to an assimilable form. While photosynthetic N2-fixers (diazotrophs) have been well-characterized, organoheterotrophic diazotrophs remain understudied despite their likely significance in satiating community N demand on local to global scales. Importantly, while fixed N availability is a strong driver of N2 fixation in photoautotrophs, recent work suggests that heterotrophic diazotrophs are less sensitive to ambient fixed N concentrations, particularly in organic-rich environments. Here, we introduce a mathematical model to predict the behavior of free-living heterotrophic diazotrophs across the aquatic continuum, coupling Monod- and Droop-type functions to predict elemental fluxes with a Gibbs Energy Dissipation model to calculate growth yields from first principles. We will present simulations from the model exploring population steady state conditions under variable chemical (N, C, O) environments and/or physiological traits.
Primary Presenter: Rebecca Everett, Haverford College (reverett@haverford.edu)
Authors:
Rebecca Everett, Haverford College (reverett@haverford.edu)
Corday Selden, Rutgers University (crselden@marine.rutgers.edu)
Mohamed Hatha Abdulla, Cochin University of Science and Technology (mohamedhatha@cusat.ac.in)
Jabir Thajudeen, National Centre for Polar and Ocean Research (jabir@ncpor.res.in)
James Powell, Sea to Shore Alliance (jpowell@sea2shore.org)
Edwin Cruz-Rivera, Morgan State University (edwin.cruz-rivera@morgan.edu)
Luca Schenone, INIBIOMA (CONICET-UNCo) (lucaschenone@comahue-conicet.gob.ar)
Renn Schipper, Kent State University (rschipp1@kent.edu)
Megan Berberich, Michigan Technological University (meberber@mtu.edu)
Halvor Halvorson, University of Central Arkansas (hhalvorson@uca.edu)
Robinson Fulweiler, Boston University (rwf@bu.edu)
Amy Marcarelli, Michigan Technological University (ammarcar@mtu.edu)
Thad Scott, Baylor University (thad_Scott@baylor.edu)
Mathematically modeling stoichiometric drivers of heterotrophic N2 fixation
Category
Scientific Sessions > SS14 - Exploring Nitrogen Fixation Along the Freshwater-Marine Continuum; A Joint ASLO-SFS Endeavor
Description
Time: 02:45 PM
Date: 4/6/2024
Room: Lecture Hall