Research Repository

Temperature response of Rubisco kinetics inArabidopsis thaliana: thermal breakpoints and implications for reaction mechanisms

Boyd, Ryan A and Cavanagh, Amanda P and Kubien, David S and Cousins, Asaph B (2019) 'Temperature response of Rubisco kinetics inArabidopsis thaliana: thermal breakpoints and implications for reaction mechanisms.' Journal of Experimental Botany, 70 (1). 231 - 242. ISSN 0022-0957

[img]
Preview
Text
ery355.pdf - Published Version
Available under License Creative Commons Attribution.

Download (738kB) | Preview

Abstract

Enhancement of Rubisco kinetics could improve photosynthetic efficiency, ultimately resulting in increased crop yield. However, imprecise knowledge of the reaction mechanism and the individual rate constants limits our ability to optimize the enzyme. Membrane inlet mass spectrometry (MIMS) may offer benefits over traditional methods for determining individual rate constants of the Rubisco reaction mechanism, as it can directly monitor concentration changes in CO2, O2, and their isotopologs during assays. However, a direct comparison of MIMS with the traditional radiolabel method of determining Rubisco kinetic parameters has not been made. Here, the temperature responses of Rubisco kinetic parameters from Arabidopsis thaliana were measured using radiolabel and MIMS methods. The two methods provided comparable parameters above 25 °C, but temperature responses deviated at low temperature as MIMS-derived catalytic rates of carboxylation, oxygenation, and CO2/O2 specificity showed thermal breakpoints. Here, we discuss the variability and uncertainty surrounding breakpoints in the Rubisco temperature response and the relevance of individual rate constants of the reaction mechanisms to potential breakpoints.

Item Type: Article
Uncontrolled Keywords: Arabidopsis, kinetic breakpoints, membrane inlet mass spectrometery, reaction mechanisms, Rubisco, temperature
Divisions: Faculty of Science and Health > Life Sciences, School of
Depositing User: Elements
Date Deposited: 11 Dec 2020 15:21
Last Modified: 11 Dec 2020 15:21
URI: http://repository.essex.ac.uk/id/eprint/28715

Actions (login required)

View Item View Item