P29639 (CYB_PITSO) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Cytochrome b

Alternative name(s):
Complex III subunit 3
Complex III subunit III
Cytochrome b-c1 complex subunit 3
Ubiquinol-cytochrome-c reductase complex cytochrome b subunit

Gene names

Name:	MT-CYB
Synonyms:	COB, CYTB, MTCYB

Encoded on

Mitochondrion

Organism

Pitta sordida (Hooded pitta)

Taxonomic identifier

9163 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Sauropsida › Sauria › Archosauria › Dinosauria › Saurischia › Theropoda › Coelurosauria › Aves › Neognathae › Passeriformes › Pittidae › Pitta

Protein attributes

Sequence length	308 AA.
Sequence status	Fragment.
Protein existence	Inferred from homology

General annotation (Comments)

Function	Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is a respiratory chain that generates an electrochemical potential coupled to ATP synthesis By similarity.
Cofactor	Binds 2 heme groups non-covalently By similarity.
Subunit structure	The bc1 complex contains 11 subunits: 3 respiratory subunits (cytochrome b, cytochrome c1 and Rieske/UQCRFS1), 2 core proteins (UQCRC1/QCR1 and UQCRC2/QCR2) and 6 low-molecular weight proteins (UQCRH/QCR6, UQCRB/QCR7, UQCRQ/QCR8, UQCR10/QCR9, UQCR11/QCR10 and a cleavage product of Rieske/UQCRFS1) By similarity.
Subcellular location	Mitochondrion inner membrane; Multi-pass membrane protein By similarity.
Miscellaneous	Heme 1 (or BL or b562) is low-potential and absorbs at about 562 nm, and heme 2 (or BH or b566) is high-potential and absorbs at about 566 nm By similarity.
Sequence similarities	Belongs to the cytochrome b family.

Ontologies

Keywords
Biological process	Electron transport Respiratory chain Transport
Cellular component	Membrane Mitochondrion Mitochondrion inner membrane
Domain	Transmembrane Transmembrane helix
Ligand	Heme Iron Metal-binding
Gene Ontology (GO)
Biological_process	respiratory electron transport chain Inferred from electronic annotation. Source: InterPro
Cellular_component	integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW mitochondrial inner membrane Inferred from electronic annotation. Source: UniProtKB-SubCell respiratory chain Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	electron carrier activity Inferred from electronic annotation. Source: InterPro metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW oxidoreductase 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
	Chain	‹1 – ›308	›308	Cytochrome b		PRO_0000061404
Regions
	Transmembrane	1 – 21	21	Helical; Potential
	Transmembrane	56 – 76	21	Helical; Potential
	Transmembrane	84 – 104	21	Helical; Potential
	Transmembrane	117 – 137	21	Helical; Potential
	Transmembrane	146 – 166	21	Helical; Potential
	Transmembrane	197 – 217	21	Helical; Potential
	Transmembrane	256 – 276	21	Helical; Potential
	Transmembrane	287 – 307	21	Helical; Potential
Sites
	Metal binding	51	1	Iron 1 (heme b562 axial ligand)
	Metal binding	65	1	Iron 2 (heme b566 axial ligand)
	Metal binding	150	1	Iron 1 (heme b562 axial ligand)
	Metal binding	164	1	Iron 2 (heme b566 axial ligand)
Experimental info
	Non-terminal residue	1	1
	Non-terminal residue	308	1

Sequences

	Sequence		Length	Mass (Da)
	P29639 [UniParc]. Last modified April 1, 1993. Version 1. Checksum: AD5FEEDB6A84EEE4	FASTA	308	34,448
	10 20 30 40 50 60 FGSLLGICLL TQILTGLLLA THYTADTTLA FSSVAHTCRN VQFGWLIRNL HANGASFFFI 70 80 90 100 110 120 CIYLHIGRGF YYGSYLNKET WNTGVILLLT LMATAFVGYA LPWGQMSFWG ATVITNLFSA 130 140 150 160 170 180 IPYMGQTLVE WAWGGFXGDN PTLTRFFALH FLLPFIIASL TLIHLTFLHE TGSNNPLGVQ 190 200 210 220 230 240 SNCDKIPFHP YLSSKDILGF MIMLLPLMTL AMFSPNLLGD PENFTPANPL VTPPHIKPEW 250 260 270 280 290 300 YFLFAYAILR SIPNKLGGVL ALAASVLILF LMPFLHKSKQ RTMTFRPLSQ LLYWTLVANL LILTWVGS

References

[1]	"Mitochondrial resolution of a deep branch in the genealogical tree for perching birds." Edwards S.V., Arctander P., Wilson A.C. Proc. R. Soc. B 243:99-107(1991) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	X60948 Genomic DNA. Translation: CAA43283.1.
PIR	S22930.
3D structure databases
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Phylogenomic databases
HOVERGEN	HBG017694.
Family and domain databases
InterPro	IPR016175. Cyt_b/b6. IPR005798. Cyt_b/b6_C. IPR005797. Cyt_b/b6_N. IPR016174. Di-haem_cyt_TM. [Graphical view]
PANTHER	PTHR19271. PTHR19271. 1 hit.
Pfam	PF00032. Cytochrom_B_C. 1 hit. PF13631. Cytochrom_B_N_2. 1 hit. [Graphical view]
SUPFAM	SSF81648. Cytochrome_b/b6_C. 1 hit. SSF81342. Transmembr_di-haem_cytochrome. 1 hit.
PROSITE	PS51003. CYTB_CTER. 1 hit. PS51002. CYTB_NTER. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

CYB_PITSO

Accession

Primary (citable) accession number: P29639

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 1, 1993
Last sequence update:	April 1, 1993
Last modified:	May 1, 2013
This is version 67 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program