The Macromolecular Basis of Phytoplankton C:N:P Under Nitrogen Starvation
Name
fmicb-10-00763.pdf
Description
Published version
Size
3.26 MB
Format
Adobe PDF
Checksum (MD5)
7cd38b5b4b4bf7abbfff519397168e63
Author(s)
Liefer, Justin D.
Garg, Aneri
Fyfe, Matthew H.
Irwin, Andrew J.
Benner, Ina
Brown, Christopher M.
Follows, Michael J
Omta, Anne Willem
Finkel, Zoe V.
Date Issued
April 2019
Journal
Frontiers in Microbiology
Publisher
Frontiers Media
Citation
Liefer, Justin D. et al. "The Macromolecular Basis of Phytoplankton C:N:P Under Nitrogen Starvation." Frontiers in Microbiology 10 (April 2019): 763 © 2019 The Author(s)
Version
Final published version
Abstract
Biogeochemical cycles in the ocean are strongly affected by the elemental stoichiometry (C:N:P) of phytoplankton, which largely reflects their macromolecular content. A greater understanding of how this macromolecular content varies among phytoplankton taxa and with resource limitation may strengthen physiological and biogeochemical modeling efforts. We determined the macromolecular basis (protein, carbohydrate, lipid, nucleic acids, pigments) of C:N:P in diatoms and prasinophytes, two globally important phytoplankton taxa, in response to N starvation. Despite their differing cell sizes and evolutionary histories, the relative decline in protein during N starvation was similar in all four species studied and largely determined variations in N content. The accumulation of carbohydrate and lipid dominated the increase in C content and C:N in all species during N starvation, but these processes differed greatly between diatoms and prasinophytes. Diatoms displayed far greater accumulation of carbohydrate with N starvation, possibly due to their greater cell size and storage capacity, resulting in larger increases in C content and C:N. In contrast, the prasinophytes had smaller increases in C and C:N that were largely driven by lipid accumulation. Variation in C:P and N:P was species-specific and mainly determined by residual P pools, which likely represent intracellular storage of inorganic P and accounted for the majority of cellular P in all species throughout N starvation. Our findings indicate that carbohydrate and lipid accumulation may play a key role in determining the environmental and taxonomic variability in phytoplankton C:N. This quantitative assessment of macromolecular and elemental content spanning several marine phytoplankton species can be used to develop physiological models for ecological and biogeochemical applications.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution 4.0 International license
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DOI of Published Version
https://doi.org/10.3389/fmicb.2019.00763
