EMD-60026

Single-particle
2.9 Å
EMD-60026 Deposition: 06/05/2024
Map released: 19/06/2024
Last modified: 03/07/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-60026

Cryo-EM structure of an intermediate-state PSII-PRF2' complex during the process of photosystem II repair

EMD-60026

Single-particle
2.9 Å
EMD-60026 Deposition: 06/05/2024
Map released: 19/06/2024
Last modified: 03/07/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Chlamydomonas reinhardtii
Sample: Cryo-EM map of the PSII-PRF2' complex functioning in the PSII-repair cycle
Fitted models: 8zee (Avg. Q-score: 0.518)

Deposition Authors: Li A , Liu Z , Liu Z
Structural basis for an early stage of the photosystem II repair cycle in Chlamydomonas reinhardtii.
Li A , You T , Pang X , Wang Y , Tian L , Li X , Liu Z
(2024) Nat Commun , 15 , 5211 - 5211
PUBMED: 38890314
DOI: doi:10.1038/s41467-024-49532-2
ISSN: 2041-1723
Abstract:
Photosystem II (PSII) catalyzes water oxidation and plastoquinone reduction by utilizing light energy. It is highly susceptible to photodamage under high-light conditions and the damaged PSII needs to be restored through a process known as the PSII repair cycle. The detailed molecular mechanism underlying the PSII repair process remains mostly elusive. Here, we report biochemical and structural features of a PSII-repair intermediate complex, likely arrested at an early stage of the PSII repair process in the green alga Chlamydomonas reinhardtii. The complex contains three protein factors associated with a damaged PSII core, namely Thylakoid Enriched Factor 14 (TEF14), Photosystem II Repair Factor 1 (PRF1), and Photosystem II Repair Factor 2 (PRF2). TEF14, PRF1 and PRF2 may facilitate the release of the manganese-stabilizing protein PsbO, disassembly of peripheral light-harvesting complexes from PSII and blockage of the QB site, respectively. Moreover, an α-tocopherol quinone molecule is located adjacent to the heme group of cytochrome b559, potentially fulfilling a photoprotective role by preventing the generation of reactive oxygen species.