Structure of Dunaliella Photosystem II reveals conformational flexibility of stacked and unstacked supercomplexes

Photosystem II (PSII) generates an oxidant whose redox potential is high enough to enable water oxidation, a substrate so abundant that it assures a practically unlimited electron source for life on earth. Our knowledge on the mechanism of water photooxidation was greatly advanced by high-resolution structures of prokaryotic PSII. Here we show high-resolution structures of eukaryotic PSII from the green algae Dunaliella salina at two distinct conformations. The conformers are also present in stacked PSII, exhibiting flexibility that is relevant to the grana formation in chloroplasts of the green lineage. CP29, one of PSII associated light harvesting antennae, plays a major role in distinguishing the two conformations of the supercomplex. We also show that the stacked PSII dimer, a form suggested to support the organization of thylakoid membranes, can appear in many different orientations providing a flexible stacking mechanism for the arrangement of grana stacks in thylakoids. Our findings provide a structural basis for the heterogenous nature of the eukaryotic PSII on multiple levels.

New Deep Hole-Trapping Site for Water Splitting on Rutile TiO2(110) Surface

Mechanism of water photooxidation reaction on the rutile TiO2(110) surface has been extensively discussed but still remains highly controversial. By ab initio many-body Green’s function theory, we discover a new...

A comprehensive understanding of water photooxidation on Ag3PO4 surfaces

A systematic study of the mechanism of OER on Ag3PO4 surfaces by combining hybrid DFT calculations and first principles thermodynamics.

Improving the photo-oxidative capability of BiOBr via crystal facet engineering

An increased presence of the {010} facet improved the performance of BiOBr for both water photooxidation and formic acid photodegradation.

New insights into water photooxidation on reductively pretreated hematite photoanodes

Photoactivity enhancement of hematite nanorod electrodes upon a reductive pretreatment can be explained on the basis of morphological and electronic changes.