Reviewed, UniProtKB/Swiss-Prot Q5CC92 (UCRIB_CYAPA)

Names and origin

Protein names

Recommended name:
    Cytochrome b6-f complex iron-sulfur subunit 2, cyanelle
    EC=1.10.99.1
Alternative name(s):
    Rieske iron-sulfur protein 2
      Short name=RISP 2
      Short name=ISP 2
    Plastohydroquinone:plastocyanin oxidoreductase iron-sulfur protein 2

Gene names

Name:

petC-2

Organism

Cyanophora paradoxa

Taxonomic identifier

2762 [NCBI]

Taxonomic lineage

Eukaryota › Glaucocystophyceae › Cyanophoraceae › Cyanophora

Protein attributes

Sequence length	241 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-1 + 2 oxidized plastocyanin = plastoquinone + 2 reduced plastocyanin.
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 › cyanelle 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	Cyanelle Membrane Plastid Thylakoid
Domain	Transit peptide Transmembrane
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 transport Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	cyanelle Inferred from electronic annotation. Source: UniProtKB-KW integral to membrane Inferred from electronic annotation. Source: UniProtKB-SubCell thylakoid membrane Inferred from electronic annotation. Source: InterPro
Molecular function	2 iron, 2 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW electron carrier activity Inferred from electronic annotation. Source: InterPro iron 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 – 62	62	Cyanelle Potential
	Chain	63 – 241	179	Cytochrome b6-f complex iron-sulfur subunit 2, cyanelle		PRO_0000030688
Regions
	Transmembrane	83 – 103	21	Potential
	Domain	127 – 223	97	Rieske
Sites
	Metal binding	169	1	Iron-sulfur (2Fe-2S) By similarity
	Metal binding	171	1	Iron-sulfur (2Fe-2S); via pros nitrogen By similarity
	Metal binding	187	1	Iron-sulfur (2Fe-2S) By similarity
	Metal binding	190	1	Iron-sulfur (2Fe-2S); via pros nitrogen By similarity
Amino acid modifications
	Disulfide bond	174 ↔ 189		By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q5CC92-1 [UniParc]. Last modified April 12, 2005. Version 1. Checksum: 05D05D37A9DADACE	FASTA	241	24,837
	10 20 30 40 50 60 MSAFACSAVA APARGAIKAN SSSVCAIENG KAVAVGTSKQ VGAFKPVFAA AKAAKATTFS 70 80 90 100 110 120 ISCSAASDEV PDMGKRKLMN LLLLGAIAGP TIGAGGPFVS FLVPPKSGGG AGAGQAAKDA 130 140 150 160 170 180 AGNDIKVEKW LETXKPGDRS LAQGLKGDAT YLIVKEDGTL EKYGLNAVCT HLGCVVPWNQ 190 200 210 220 230 240 SEGKFMCPCH GSQYDRTGKV VRGPAPLSLA LAHVNVLEDG VVAFEPWTET DFRTNTAPWW K

References

[1]

"Conservative sorting in a primitive plastid. The cyanelle of Cyanophora paradoxa." Steiner J.M., Berghoefer J., Yusa F., Pompe J.A., Kloesgen R.B., Loeffelhardt W. FEBS J. 272:987-998(2005) [PubMed: 15691332] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN IMPORT INTO ISOLATED CYANELLES. Strain: UTEX LB 555 / Pringsheim.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AJ784853 mRNA. Translation: CAH04961.1.
3D structure databases
ModBase	Search...
Enzyme and pathway databases
BRENDA	1.10.99.1. 11.
Family and domain databases
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]
Gene3D	G3DSA:2.102.10.10. Rieske_reg. 1 hit.
PANTHER	PTHR10134. Rieske. 1 hit.
Pfam	PF08802. CytB6-F_Fe-S. 1 hit. PF00355. Rieske. 1 hit. [Graphical view]
PRINTS	PR00162. RIESKE.
PROSITE	PS51296. RIESKE. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

UCRIB_CYAPA

Accession

Primary (citable) accession number: Q5CC92

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 5, 2005
Last sequence update:	April 12, 2005
Last modified:	October 13, 2009
This is version 33 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)