CYB6_SPIOL
ID CYB6_SPIOL Reviewed; 215 AA.
AC P00165;
DT 21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1988, sequence version 1.
DT 03-AUG-2022, entry version 125.
DE RecName: Full=Cytochrome b6 {ECO:0000255|HAMAP-Rule:MF_00633};
GN Name=petB {ECO:0000255|HAMAP-Rule:MF_00633};
OS Spinacia oleracea (Spinach).
OG Plastid; Chloroplast.
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC Caryophyllales; Chenopodiaceae; Chenopodioideae; Anserineae; Spinacia.
OX NCBI_TaxID=3562;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=2834086; DOI=10.1007/bf00420602;
RA Westhoff P., Farchaus J.W., Herrmann R.G.;
RT "The gene for the Mr 10,000 phosphoprotein associated with photosystem II
RT is part of the psbB operon of the spinach plastid chromosome.";
RL Curr. Genet. 11:165-169(1986).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA Heinemeyer W., Alt J., Herrmann R.G.;
RT "Nucleotide sequence of the clustered genes for apocytochrome b6 and
RT subunit 4 of the cytochrome b/f complex in the spinach plastid
RT chromosome.";
RL Curr. Genet. 8:543-549(1984).
RN [3]
RP SEQUENCE REVISION.
RX PubMed=2831053; DOI=10.1111/j.1432-1033.1988.tb13824.x;
RA Westhoff P., Herrmann R.G.;
RT "Complex RNA maturation in chloroplasts. The psbB operon from spinach.";
RL Eur. J. Biochem. 171:551-564(1988).
RN [4]
RP PROTEIN SEQUENCE.
RX PubMed=6322162; DOI=10.1073/pnas.81.3.674;
RA Widger W.R., Cramer W.A., Herrmann R.G., Trebst A.;
RT "Sequence homology and structural similarity between cytochrome b of
RT mitochondrial complex III and the chloroplast b6-f complex: position of the
RT cytochrome b hemes in the membrane.";
RL Proc. Natl. Acad. Sci. U.S.A. 81:674-678(1984).
RN [5]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=cv. Geant d'hiver, and cv. Monatol;
RX PubMed=11292076; DOI=10.1023/a:1006478403810;
RA Schmitz-Linneweber C., Maier R.M., Alcaraz J.-P., Cottet A., Herrmann R.G.,
RA Mache R.;
RT "The plastid chromosome of spinach (Spinacia oleracea): complete nucleotide
RT sequence and gene organization.";
RL Plant Mol. Biol. 45:307-315(2001).
RN [6]
RP HEME-BINDING.
RX PubMed=12438564; DOI=10.1074/mcp.m200045-mcp200;
RA Whitelegge J.P., Zhang H., Aguilera R., Taylor R.M., Cramer W.A.;
RT "Full subunit coverage liquid chromatography electrospray ionization mass
RT spectrometry (LCMS+) of an oligomeric membrane protein: cytochrome b(6)f
RT complex from spinach and the cyanobacterium Mastigocladus laminosus.";
RL Mol. Cell. Proteomics 1:816-827(2002).
CC -!- FUNCTION: Component of the cytochrome b6-f complex, which mediates
CC electron transfer between photosystem II (PSII) and photosystem I
CC (PSI), cyclic electron flow around PSI, and state transitions.
CC {ECO:0000255|HAMAP-Rule:MF_00633}.
CC -!- COFACTOR:
CC Name=heme; Xref=ChEBI:CHEBI:30413;
CC Note=Binds 2 heme groups. One heme group is bound covalently by a
CC single cysteine link, the other one non-covalently.;
CC -!- SUBUNIT: The 4 large subunits of the cytochrome b6-f complex are
CC cytochrome b6, subunit IV (17 kDa polypeptide, PetD), cytochrome f and
CC the Rieske protein, while the 4 small subunits are PetG, PetL, PetM and
CC PetN. The complex functions as a dimer. {ECO:0000255|HAMAP-
CC Rule:MF_00633}.
CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast thylakoid membrane
CC {ECO:0000255|HAMAP-Rule:MF_00633}; Multi-pass membrane protein
CC {ECO:0000255|HAMAP-Rule:MF_00633}.
CC -!- MISCELLANEOUS: Heme 1 (or BH or b566) is high-potential and absorbs at
CC about 566 nm, and heme 2 (or BL or b562) is low-potential and absorbs
CC at about 562 nm.
CC -!- SIMILARITY: Belongs to the cytochrome b family. PetB subfamily.
CC {ECO:0000255|HAMAP-Rule:MF_00633}.
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DR EMBL; X07106; CAA30128.1; -; Genomic_DNA.
DR EMBL; AJ400848; CAB88757.1; -; Genomic_DNA.
DR PIR; S03021; CBSP6.
DR RefSeq; NP_054964.1; NC_002202.1.
DR PDB; 6RQF; EM; 3.58 A; A/I=1-215.
DR PDBsum; 6RQF; -.
DR AlphaFoldDB; P00165; -.
DR SMR; P00165; -.
DR IntAct; P00165; 7.
DR STRING; 3562.P00165; -.
DR GeneID; 2715598; -.
DR KEGG; soe:2715598; -.
DR OrthoDB; 1125966at2759; -.
DR Proteomes; UP000054095; Chloroplast.
DR GO; GO:0009535; C:chloroplast thylakoid membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0045158; F:electron transporter, transferring electrons within cytochrome b6/f complex of photosystem II activity; IEA:UniProtKB-UniRule.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0015979; P:photosynthesis; IEA:UniProtKB-UniRule.
DR GO; GO:0022904; P:respiratory electron transport chain; IEA:InterPro.
DR CDD; cd00284; Cytochrome_b_N; 1.
DR Gene3D; 1.20.810.10; -; 1.
DR HAMAP; MF_00633; Cytb6_f_cytb6; 1.
DR InterPro; IPR005797; Cyt_b/b6_N.
DR InterPro; IPR023530; Cyt_B6_PetB.
DR InterPro; IPR027387; Cytb/b6-like_sf.
DR InterPro; IPR016174; Di-haem_cyt_TM.
DR PANTHER; PTHR19271:SF20; PTHR19271:SF20; 1.
DR Pfam; PF00033; Cytochrome_B; 1.
DR SUPFAM; SSF81342; SSF81342; 1.
DR PROSITE; PS51002; CYTB_NTER; 1.
PE 1: Evidence at protein level;
KW 3D-structure; Chloroplast; Direct protein sequencing; Electron transport;
KW Heme; Iron; Membrane; Metal-binding; Photosynthesis; Plastid;
KW Reference proteome; Thylakoid; Transmembrane; Transmembrane helix;
KW Transport.
FT CHAIN 1..215
FT /note="Cytochrome b6"
FT /id="PRO_0000061821"
FT TRANSMEM 32..52
FT /note="Helical"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00633"
FT TRANSMEM 90..110
FT /note="Helical"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00633"
FT TRANSMEM 116..136
FT /note="Helical"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00633"
FT TRANSMEM 186..206
FT /note="Helical"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00633"
FT BINDING 35
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_label="1"
FT /note="covalent"
FT BINDING 86
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_label="2"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT BINDING 100
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_label="1"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT BINDING 187
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_label="2"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT BINDING 202
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_label="1"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT CONFLICT 108..109
FT /note="Missing (in Ref. 4; AA sequence)"
FT /evidence="ECO:0000305"
FT CONFLICT 188
FT /note="Missing (in Ref. 4; AA sequence)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 215 AA; 24167 MW; A4518BF715B62F7D CRC64;
MSKVYDWFEE RLEIQAIADD ITSKYVPPHV NIFYCLGGIT LTCFLVQVAT GFAMTFYYRP
TVTDAFASVQ YIMTEVNFGW LIRSVHRWSA SMMVLMMILH VFRVYLTGGF KKPRELTWVT
GVVLGVLTAS FGVTGYSLPW DQIGYWAVKI VTGVPDAIPV IGSPLVELLR GSASVGQSTL
TRFYSLHTFV LPLLTAVFML MHFLMIRKQG ISGPL
