The manganese-stabilizing protein is required for photosystem II assembly/stability and photoautotrophy in higher plants.

Interfering RNA was used to suppress the expression of two genes that encode the manganese-stabilizing protein of photosystem II in Arabidopsis thaliana, MSP-1 (encoded by psbO-1, At5g66570), and MSP-2 (encoded by psbO-2, At3g50820). A phenotypic series of transgenic plants was recovered that expressed high, intermediate, and low amounts of these two manganese-stabilizing proteins. Chlorophyll fluorescence induction and decay analyses were performed.

Alterations of the oxygen-evolving apparatus induced by a 305Arg --> 305Ser mutation in the CP43 protein of photosystem II from Synechocystis sp. PCC 6803 under chloride-limiting conditions.

The psbC gene encodes CP43, a component of Photosystem II (PSII) in higher plants, algae, and cyanobacteria. Previous work demonstrated that alteration of an arginine residue occurring at position 305 to serine produced a strain (R305S) with altered PSII activity (Knoepfle, N., Bricker, T.