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.