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New Structural and Mechanistic Insights Into Functional Roles of Cytochrome b ₅₅₉ in Photosystem II.

ABSTRACT: Cytochrome (Cyt) b ₅₅₉ is a key component of the photosystem II (PSII) complex for its assembly and proper function. Previous studies have suggested that Cytb ₅₅₉ has functional roles in early assembly of PSII and in secondary electron transfer pathways that protect PSII against photoinhibition. In addition, the Cytb ₅₅₉ in various PSII preparations exhibited multiple different redox potential forms. However, the precise functional roles of Cytb ₅₅₉ in PSII remain unclear. Recent site-directed mutagenesis studies combined with functional genomics and biochemical analysis, as well as high-resolution x-ray crystallography and cryo-electron microscopy studies on native, inactive, and assembly intermediates of PSII have provided important new structural and mechanistic insights into the functional roles of Cytb ₅₅₉. This mini-review gives an overview of new exciting results and their significance for understanding the structural and functional roles of Cytb ₅₅₉ in PSII.

SUBMITTER: Chiu YF

PROVIDER: S-EPMC9214863 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Author Correction: Structural evidence for intermediates during O2 formation in photosystem II.

Project description: Not available

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