Research Repository

An integrated response of Trichodesmium erythraeum IMS101 growth and photo-physiology to Iron, CO₂, and light intensity

Boatman, TG and Oxborough, K and Gledhill, M and Lawson, T and Geider, RJ (2018) 'An integrated response of Trichodesmium erythraeum IMS101 growth and photo-physiology to Iron, CO₂, and light intensity.' Frontiers in Microbiology, 9. ISSN 1664-302X

[img]
Preview
Text
fmicb-09-00624.pdf - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview

Abstract

We have assessed how varying CO 2 (180, 380, and 720 μatm) and growth light intensity (40 and 400 μmol photons m -2 s -1 ) affected Trichodesmium erythraeum IMS101 growth and photophysiology over free iron (Fe') concentrations between 20 and 9,600 pM. We found significant iron dependencies of growth rate and the initial slope and maximal relative PSII electron transport rates (rP m ). Under iron-limiting concentrations, high-light increased growth rates and rPm; possibly indicating a lower allocation of resources to iron-containing photosynthetic proteins. Higher CO 2 increased growth rates across all iron concentrations, enabled growth to occur at lower Fe' concentrations, increased rPm and lowered the iron half saturation constants for growth (K m ). We attribute these CO 2 responses to the operation of the CCM and the ATP spent/saved for CO 2 uptake and transport at low and high CO 2 , respectively. It seems reasonable to conclude that T. erythraeum IMS101 can exhibit a high degree of phenotypic plasticity in response to CO 2 , light intensity and iron-limitation. These results are important given predictions of increased dissolved CO 2 and water column stratification (i.e., higher light exposures) over the coming decades.

Item Type: Article
Uncontrolled Keywords: Trichodesmium erythraeum, Cyanobacteria, ocean acidification, CO2, iron limitation, light intensity, fluorescence light curves, electron transport rates
Subjects: Q Science > QH Natural history > QH301 Biology
Divisions: Faculty of Science and Health > Life Sciences, School of
Depositing User: Elements
Date Deposited: 24 Apr 2018 14:54
Last Modified: 06 Sep 2019 21:15
URI: http://repository.essex.ac.uk/id/eprint/21884

Actions (login required)

View Item View Item