Accession	MF_01335
Dates	2-JUN-2005 (Created) 30-JUN-2008 (Last updated, Version 20)

Data class

Protein

Predictors

HAMAP; MF_01335; [distribution of match scores in UniProtKB];[seed alignment for MF_01335]

Identifier

UCRI

Protein name

RecName: Full=Cytochrome b6-f complex iron-sulfur subunit; EC=1.10.99.1; AltName: Full=Rieske iron-sulfur protein; AltName: Full=Plastohydroquinone:plastocyanin oxidoreductase iron-sulfur protein; Short=ISP; Short=RISP;

Gene name

petC

FUNCTION: Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions (By similarity).

CATALYTIC ACTIVITY: Plastoquinol-1 + 2 oxidized plastocyanin = plastoquinone + 2 reduced plastocyanin.

COFACTOR: Binds 1 2Fe-2S cluster per subunit (By similarity).

SUBUNIT: The 4 large subunits of the cytochrome b6-f complex are cytochrome b6, subunit IV (17 kDa polypeptide, petD), cytochrome f and the Rieske protein, while the 4 small subunits are petG, petL, petM and petN. The complex functions as a dimer (By similarity).

SUBCELLULAR LOCATION: Cellular thylakoid membrane; Single-pass membrane protein (By similarity). Note=The transmembrane helix obliquely spans the membrane in one monomer, and its extrinsic C-terminal domain is part of the other monomer (By similarity).

SUBCELLULAR LOCATION: Cell inner membrane; Single-pass membrane protein (By similarity). Note=The transmembrane helix obliquely spans the membrane in one monomer, and its extrinsic C-terminal domain is part of the other monomer (By similarity).

MISCELLANEOUS: The Rieske iron-sulfur protein is a high potential 2Fe-2S protein.

SIMILARITY: Contains 1 Rieske domain.

PROSITE	PS51296; RIESKE; 1; trigger=PRU00628; PS51318; TAT; 0-1;
Pfam	PF00355; Rieske; 1;
PRINTS	PR00162; RIESKE; 1;
TIGRFAMs	TIGR01409; TAT_signal_seq; 1;
General	Transmembrane; -; 1; trigger=Yes;

Electron transport.

Thylakoid.

Cell membrane, Cell inner membrane.

2Fe-2S, Iron, Iron-sulfur, Metal-binding.

Membrane, Oxidoreductase, Transmembrane, Transport.

GO:0045158; Molecular function: electron transporter, transferring electrons within cytochrome b6/f complex of photosystem II activity.
GO:0009496; Molecular function: plastoquinol-plastocyanin reductase activity.
GO:0015979; Biological process: photosynthesis.
GO:0055114; Biological process: oxidation reduction.

GO:0042651; Cellular component: thylakoid membrane.

GO:0005886; Cellular component: plasma membrane.

Size range:	172-186 amino acids
Related UniRules:	None
Template:	P83794 (UCRI_MASLA); P49728 (UCRIA_CHLRE): [Recover all]
Scope:	Bacteria; Cyanobacteria
Fusion:	Nter: None; Cter: None
Duplicate:	in ANASP, ANAVA, SYNY3
Plasmid encoded:	None
Comments:	May be translocated into the membrane by the TAT pathway but without signal cleavage. In some cases a TAT signal is not recognized by either the PROSITE or TIGRFAMs predictors.