Q9SBN3 (UCRIA_VOLCA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Cytochrome b6-f complex iron-sulfur subunit, chloroplastic
EC=1.10.9.1

Alternative name(s):
Plastohydroquinone:plastocyanin oxidoreductase iron-sulfur protein
Rieske iron-sulfur protein
Short name=ISP
Short name=RISP

Gene names

Name:

petC

Organism

Volvox carteri (Green alga)

Taxonomic identifier

3067 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Viridiplantae › Chlorophyta › Chlorophyceae › Chlamydomonadales › Volvocaceae › Volvox

Protein attributes

Sequence length	206 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at transcript level

General annotation (Comments)

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 + 2 oxidized plastocyanin + 2 H+(Side 1) = plastoquinone + 2 reduced plastocyanin + 2 H+(Side 2).
Cofactor	Binds 1 2Fe-2S cluster per subunit By similarity.
Subunit structure	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	Plastid › chloroplast 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.
Miscellaneous	This protein is 1 of 2 subunits of the cytochrome b6-f complex that are encoded in the nucleus. The Rieske iron-sulfur protein is a high potential 2Fe-2S protein.
Sequence similarities	Contains 1 Rieske domain.

Ontologies

Keywords
Biological process	Electron transport Transport
Cellular component	Chloroplast Membrane Plastid Thylakoid
Domain	Transit peptide Transmembrane Transmembrane helix
Ligand	2Fe-2S Iron Iron-sulfur Metal-binding
Molecular function	Oxidoreductase
PTM	Disulfide bond
Gene Ontology (GO)
Biological_process	electron transport chain Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	chloroplast thylakoid membrane Inferred from electronic annotation. Source: UniProtKB-SubCell integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	2 iron, 2 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW plastoquinol--plastocyanin reductase activity Inferred from electronic annotation. Source: EC ubiquinol-cytochrome-c reductase activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Transit peptide	1 – 29	29	Chloroplast By similarity
	Chain	30 – 206	177	Cytochrome b6-f complex iron-sulfur subunit, chloroplastic		PRO_0000030696
Regions
	Transmembrane	48 – 68	21	Helical; Potential
	Domain	92 – 188	97	Rieske
	Compositional bias	74 – 79	6	Poly-Gly
Sites
	Metal binding	134	1	Iron-sulfur (2Fe-2S) By similarity
	Metal binding	136	1	Iron-sulfur (2Fe-2S); via pros nitrogen By similarity
	Metal binding	152	1	Iron-sulfur (2Fe-2S) By similarity
	Metal binding	155	1	Iron-sulfur (2Fe-2S); via pros nitrogen By similarity
Amino acid modifications
	Disulfide bond	139 ↔ 154		By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q9SBN3 [UniParc]. Last modified May 1, 2000. Version 1. Checksum: EB6D9E269D2131BD	FASTA	206	21,676
	10 20 30 40 50 60 MAMITSRRAA APCKAQATRR SRVMSVVRAA AVSSEVPDMN KRNIMNLILL GGASLPVGSL 70 80 90 100 110 120 ALGYGAFFVP PSSGGGSGGQ AAKDALGNDI KANAWLATHQ KGDRSLSQGL KGDPTYLIVT 130 140 150 160 170 180 ADGTIEKYGL NAVCTHLGCV VPWVAAENKF KCPCHGSQYN AEGKVVRGPA PLSLALAHCD 190 200 VQEDGLVTFS TWSETDFRTG LEPWWA

References

[1]	"Volvox germline-specific genes that are putative targets of RegA repression encode chloroplast proteins." Meissner M., Stark K., Cresnar B., Kirk D.L., Schmitt R. Curr. Genet. 36:363-370(1999) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: f. Nagariensis.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF110783 mRNA. Translation: AAD55565.1.
RefSeq	XP_002947706.1. XM_002947660.1.
UniGene	Vca.182.
3D structure databases
ProteinModelPortal	Q9SBN3.
SMR	Q9SBN3. Positions 33-71, 80-206.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
GeneID	9620593.
KEGG	vcn:VOLCADRAFT_109628.
Phylogenomic databases
KO	K02636.
ProtClustDB	CLSN2685934.
Family and domain databases
Gene3D	2.102.10.10. 1 hit.
InterPro	IPR014909. Cyt_b6-f_cplx_Fe-S_su. IPR017941. Rieske_2Fe-2S. IPR014349. Rieske_Fe-S_prot. IPR005805. Rieske_Fe-S_prot_C. [Graphical view]
PANTHER	PTHR10134. PTHR10134. 1 hit.
Pfam	PF08802. CytB6-F_Fe-S. 1 hit. PF00355. Rieske. 1 hit. [Graphical view]
PRINTS	PR00162. RIESKE.
SUPFAM	SSF50022. Rieske_dom. 1 hit.
PROSITE	PS51296. RIESKE. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

UCRIA_VOLCA

Accession

Primary (citable) accession number: Q9SBN3

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 1, 2000
Last sequence update:	May 1, 2000
Last modified:	May 1, 2013
This is version 83 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program