eCite Digital Repository
Phytoplankton calcification as an effective mechanism to alleviate cellular calcium poisoning
Citation
Muller, MN and Barcelos e Ramos, J and Schulz, KG and Riebesell, U and Kazmierczak, J and Gallo, F and Mackinder, L and Li, Y and Nesterenko, PN and Trull, TW and Hallegraeff, GM, Phytoplankton calcification as an effective mechanism to alleviate cellular calcium poisoning, Biogeosciences, 12, (21) pp. 6493-6501. ISSN 1726-4170 (2015) [Refereed Article]
 | PDF 202Kb |
Copyright Statement
Copyright 2015 The Authors Licensed under Creative Commons Attribution 3.0 Unported (CC BY 3.0) https://creativecommons.org/licenses/by/3.0/
DOI: doi:10.5194/bg-12-6493-2015
Abstract
Marine phytoplankton have developed the remarkable ability to tightly
regulate the concentration of free calcium ions in the intracellular cytosol
at a level of ~ 0.1 μmol L−1 in the presence of
seawater Ca2+ concentrations of 10 mmol L−1. The low cytosolic
calcium ion concentration is of utmost importance for proper cell signalling
function. While the regulatory mechanisms responsible for the tight control
of intracellular Ca2+ concentration are not completely understood,
phytoplankton taxonomic groups appear to have evolved different strategies,
which may affect their ability to cope with changes in seawater Ca2+
concentrations in their environment on geological timescales. For example,
the Cretaceous (145 to 66 Ma), an era known for the high abundance of
coccolithophores and the production of enormous calcium carbonate deposits,
exhibited seawater calcium concentrations up to 4 times present-day
levels. We show that calcifying coccolithophore species (Emiliania huxleyi, Gephyrocapsa oceanica and Coccolithus braarudii) are able
to maintain their relative fitness (in terms of growth rate and
photosynthesis) at simulated Cretaceous seawater calcium concentrations, whereas these rates are severely reduced under these
conditions in some non-calcareous phytoplankton species (Chaetoceros sp., Ceratoneis closterium and
Heterosigma akashiwo). Most notably, this also applies to a non-calcifying strain of E. huxleyi which
displays a calcium sensitivity similar to the non-calcareous species. We
hypothesize that the process of calcification in coccolithophores provides
an efficient mechanism to alleviate cellular calcium poisoning and thereby
offered a potential key evolutionary advantage, responsible for the
proliferation of coccolithophores during times of high seawater calcium
concentrations. The exact function of calcification and the reason behind
the highly ornate physical structures of coccoliths remain elusive.
Item Details
| Item Type: | Refereed Article |
|---|---|
| Keywords: | coccolithophores, calcium detoxification, biomineralization |
| Research Division: | Chemical Sciences |
| Research Group: | Analytical chemistry |
| Research Field: | Separation science |
| Objective Division: | Expanding Knowledge |
| Objective Group: | Expanding knowledge |
| Objective Field: | Expanding knowledge in the chemical sciences |
| UTAS Author: | Muller, MN (Dr Marius Muller) |
| UTAS Author: | Li, Y (Mr Yan Li) |
| UTAS Author: | Nesterenko, PN (Professor Pavel Nesterenko) |
| UTAS Author: | Trull, TW (Professor Thomas Trull) |
| UTAS Author: | Hallegraeff, GM (Professor Gustaaf Hallegraeff) |
| ID Code: | 104559 |
| Year Published: | 2015 |
| Web of Science® Times Cited: | 18 |
| Deposited By: | Chemistry |
| Deposited On: | 2015-11-16 |
| Last Modified: | 2017-10-29 |
| Downloads: | 235 View Download Statistics |
Repository Staff Only: item control page