ID CYB_CHEMY Reviewed; 381 AA. AC Q9TEC1; DT 04-JAN-2005, integrated into UniProtKB/Swiss-Prot. DT 01-MAY-2000, sequence version 1. DT 27-MAY-2015, entry version 80. DE RecName: Full=Cytochrome b; DE AltName: Full=Complex III subunit 3; DE AltName: Full=Complex III subunit III; DE AltName: Full=Cytochrome b-c1 complex subunit 3; DE AltName: Full=Ubiquinol-cytochrome-c reductase complex cytochrome b subunit; GN Name=MT-CYB; Synonyms=COB, CYTB, MTCYB; OS Chelonia mydas (Green sea-turtle) (Chelonia agassizi). OG Mitochondrion. OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; OC Archelosauria; Testudines; Cryptodira; Durocryptodira; Americhelydia; OC Chelonioidea; Cheloniidae; Chelonia. OX NCBI_TaxID=8469; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RX PubMed=10368956; DOI=10.1093/oxfordjournals.molbev.a026163; RA Kumazawa Y., Nishida M.; RT "Complete mitochondrial DNA sequences of the green turtle and blue- RT tailed mole skink: statistical evidence for archosaurian affinity of RT turtles."; RL Mol. Biol. Evol. 16:784-792(1999). CC -!- FUNCTION: Component of the ubiquinol-cytochrome c reductase CC complex (complex III or cytochrome b-c1 complex), which is a CC respiratory chain that generates an electrochemical potential CC coupled to ATP synthesis. {ECO:0000250}. CC -!- COFACTOR: CC Name=heme; Xref=ChEBI:CHEBI:30413; Evidence={ECO:0000250}; CC Note=Binds 2 heme groups non-covalently. {ECO:0000250}; CC -!- SUBUNIT: The main subunits of complex b-c1 are: cytochrome b, CC cytochrome c1 and the Rieske protein. {ECO:0000250}. CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane {ECO:0000250}; CC Multi-pass membrane protein {ECO:0000250}. CC -!- MISCELLANEOUS: Heme 1 (or BL or b562) is low-potential and absorbs CC at about 562 nm, and heme 2 (or BH or b566) is high-potential and CC absorbs at about 566 nm. {ECO:0000250}. CC -!- SIMILARITY: Belongs to the cytochrome b family. CC {ECO:0000255|PROSITE-ProRule:PRU00967, ECO:0000255|PROSITE- CC ProRule:PRU00968}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; AB012104; BAA79209.1; -; Genomic_DNA. DR RefSeq; NP_008776.1; NC_000886.1. DR ProteinModelPortal; Q9TEC1; -. DR SMR; Q9TEC1; 1-379. DR GeneID; 808644; -. DR KEGG; cmy:808644; -. DR CTD; 4519; -. DR HOVERGEN; HBG017694; -. DR KO; K00412; -. DR GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell. DR GO; GO:0045275; C:respiratory chain complex III; IEA:InterPro. DR GO; GO:0009055; F:electron carrier activity; IEA:InterPro. DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW. DR GO; GO:0008121; F:ubiquinol-cytochrome-c reductase activity; IEA:InterPro. DR GO; GO:0006122; P:mitochondrial electron transport, ubiquinol to cytochrome c; IEA:InterPro. DR Gene3D; 1.20.810.10; -; 1. DR InterPro; IPR005798; Cyt_b/b6_C. DR InterPro; IPR005797; Cyt_b/b6_N. DR InterPro; IPR027387; Cytb/b6-like. DR InterPro; IPR030689; Cytochrome_b. DR InterPro; IPR016174; Di-haem_cyt_TM. DR Pfam; PF00032; Cytochrom_B_C; 1. DR Pfam; PF13631; Cytochrom_B_N_2; 1. DR PIRSF; PIRSF038885; COB; 1. DR SUPFAM; SSF81342; SSF81342; 1. DR SUPFAM; SSF81648; SSF81648; 1. DR PROSITE; PS51003; CYTB_CTER; 1. DR PROSITE; PS51002; CYTB_NTER; 1. PE 3: Inferred from homology; KW Electron transport; Heme; Iron; Membrane; Metal-binding; KW Mitochondrion; Mitochondrion inner membrane; Respiratory chain; KW Transmembrane; Transmembrane helix; Transport. FT CHAIN 1 381 Cytochrome b. FT /FTId=PRO_0000060775. FT TRANSMEM 34 54 Helical. {ECO:0000255}. FT TRANSMEM 90 110 Helical. {ECO:0000255}. FT TRANSMEM 117 137 Helical. {ECO:0000255}. FT TRANSMEM 151 171 Helical. {ECO:0000255}. FT TRANSMEM 179 199 Helical. {ECO:0000255}. FT TRANSMEM 230 250 Helical. {ECO:0000255}. FT TRANSMEM 289 309 Helical. {ECO:0000255}. FT TRANSMEM 324 344 Helical. {ECO:0000255}. FT TRANSMEM 347 367 Helical. {ECO:0000255}. FT METAL 84 84 Iron 1 (heme b562 axial ligand). FT METAL 98 98 Iron 2 (heme b566 axial ligand). FT METAL 183 183 Iron 1 (heme b562 axial ligand). FT METAL 197 197 Iron 2 (heme b566 axial ligand). SQ SEQUENCE 381 AA; 42859 MW; DE980F3AFE9E17D7 CRC64; MATNLRKTHP MMKIINNLVI DLPSPSNISA WWNFGSLLAT CLALQIITGI FLAMHYSPDI SMAFSSIAHI TRDVQYGWLI RNMHANGASL FFMCIYLHIG RGIYYGSYLY KETWNTGIIL LLLVMATAFV GYVLPWGQMS FWGATVITNL LSAIPYIGNT LVQWIWGGFS VDNATLTRFF TFHFLLPFAI TGLTAVHLLF LHETGSNNPT GLNSNTDKIP FHPYFSYKDL LGLILMLTFL LTLTLFSPYL LGDPDNFTPA NPLSTPPHIK PEWYFLFAYA ILRSIPNKLG GVLALLFSIL ILFLMPTLHT SKQRTASFRP LTQILFWSLV ADLLVLTWIG GQPVEDPFII IGQVASTFYF LILLLLMPAA GMIENKMLNL K //