CATH Classification

Domain Context

CATH Clusters

Superfamily Single helix bin
Functional Family

Enzyme Information

7.1.1.6
Plastoquinol--plastocyanin reductase.
based on mapping to UniProt P83794
Plastoquinol + 2 oxidized plastocyanin + 2 H(+)(Side 1) = plastoquinone + 2 reduced plastocyanin + 4 H(+)(Side 2).
-!- Contains two b-type cytochromes, two c-type cytochromes (c(n) and f), and a [2Fe-2S] Rieske cluster. -!- The enzyme plays a key role in photosynthesis, transferring electrons from photosystem II (EC 1.10.3.9) to photosystem I (EC 1.97.1.12). -!- Cytochrome c-552 can act as acceptor instead of plastocyanin, but more slowly. -!- In chloroplasts, protons are translocated through the thylakoid membrane from the lumen to the stroma. -!- The mechanism occurs through the Q cycle as in EC 7.1.1.8 (complex III) and involves electron bifurcation. -!- Formerly EC 1.10.9.1 and EC 1.10.99.1.

UniProtKB Entries (1)

P83792
PETD_MASLA
Mastigocladus laminosus
Cytochrome b6-f complex subunit 4

PDB Structure

PDB 4H0L
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Quinone-dependent proton transfer pathways in the photosynthetic cytochrome b6f complex
Hasan, S.S., Yamashita, E., Baniulis, D., Cramer, W.A.
Proc.Natl.Acad.Sci.USA