Regulation of peroxidase and molecular functions of 2-Cys PrxA

The 2-Cys peroxiredoxin (Prx) A protein of Arabidopsis thaliana performs the dual functions of a peroxidase and a molecular chaperone depending on its conformation and the metabolic conditions. However, the precise mechanism responsible for the functional switching of 2-Cys Prx A is poorly known.

Lee et al. generate mutants of 2-Cys Prx A by substituting serine (Ser) with cysteine (Cys) at different locations through site-directed mutagenesis and find that substitution of Ser¹⁵⁰ to Cys¹⁵⁰ remarkably improves the holdase chaperone and peroxidase activities due to conformational changes. Molecular modelling confirms the relationship between the mutation positions and switching of 2-Cys Prx A activity. If confirmed in planta, this leads to the potential for the substitution to be used to maximize the functional utility of the 2-Cys Prx A protein for improved metabolic functions and stress resistance in plants.

This article appears in the special issue ROS and NO Reactions in Plants.