CYB6_SYNP2
ID CYB6_SYNP2 Reviewed; 222 AA.
AC P28056; B1XIH5;
DT 01-AUG-1992, integrated into UniProtKB/Swiss-Prot.
DT 01-AUG-1992, sequence version 1.
DT 03-AUG-2022, entry version 147.
DE RecName: Full=Cytochrome b6;
GN Name=petB; OrderedLocusNames=SYNPCC7002_A0842;
OS Synechococcus sp. (strain ATCC 27264 / PCC 7002 / PR-6) (Agmenellum
OS quadruplicatum).
OC Bacteria; Cyanobacteria; Synechococcales; Synechococcaceae; Synechococcus;
OC unclassified Synechococcus.
OX NCBI_TaxID=32049;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=1421151; DOI=10.1007/bf00040607;
RA Brand S.N., Tan X., Widger W.R.;
RT "Cloning and sequencing of the petBD operon from the cyanobacterium
RT Synechococcus sp. PCC 7002.";
RL Plant Mol. Biol. 20:481-491(1992).
RN [2]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=ATCC 27264 / PCC 7002 / PR-6;
RA Li T., Zhao J., Zhao C., Liu Z., Zhao F., Marquardt J., Nomura C.T.,
RA Persson S., Detter J.C., Richardson P.M., Lanz C., Schuster S.C., Wang J.,
RA Li S., Huang X., Cai T., Yu Z., Luo J., Zhao J., Bryant D.A.;
RT "Complete sequence of Synechococcus sp. PCC 7002.";
RL Submitted (FEB-2008) to the EMBL/GenBank/DDBJ databases.
RN [3]
RP MUTAGENESIS OF ASP-148; ALA-154; SER-159 AND HIS-209.
RX PubMed=11245788; DOI=10.1016/s0005-2728(00)00253-x;
RA Lee T.-X., Metzger S.U., Cho Y.S., Whitmarsh J., Kallas T.;
RT "Modification of inhibitor binding sites in the cytochrome bf complex by
RT directed mutagenesis of cytochrome b(6) in Synechococcus sp. PCC 7002.";
RL Biochim. Biophys. Acta 1504:235-247(2001).
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:0000250}.
CC -!- COFACTOR:
CC Name=heme; Xref=ChEBI:CHEBI:30413; Evidence={ECO:0000250};
CC Note=Binds 2 heme groups. One heme group is bound covalently by a
CC single cysteine link, the other one non-covalently. {ECO:0000250};
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 (By similarity). {ECO:0000250}.
CC -!- SUBCELLULAR LOCATION: Cellular thylakoid membrane; Multi-pass membrane
CC protein.
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. {ECO:0000250}.
CC -!- SIMILARITY: Belongs to the cytochrome b family. PetB subfamily.
CC {ECO:0000305}.
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DR EMBL; X63049; CAA44774.1; -; Genomic_DNA.
DR EMBL; CP000951; ACA98846.1; -; Genomic_DNA.
DR RefSeq; WP_012306470.1; NC_010475.1.
DR AlphaFoldDB; P28056; -.
DR SMR; P28056; -.
DR STRING; 32049.SYNPCC7002_A0842; -.
DR EnsemblBacteria; ACA98846; ACA98846; SYNPCC7002_A0842.
DR KEGG; syp:SYNPCC7002_A0842; -.
DR eggNOG; COG1290; Bacteria.
DR HOGENOM; CLU_031114_0_2_3; -.
DR OMA; WATQTGM; -.
DR Proteomes; UP000001688; Chromosome.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0031676; C:plasma membrane-derived thylakoid membrane; IEA:UniProtKB-SubCell.
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 Electron transport; Heme; Iron; Membrane; Metal-binding; Photosynthesis;
KW Reference proteome; Thylakoid; Transmembrane; Transmembrane helix;
KW Transport.
FT CHAIN 1..222
FT /note="Cytochrome b6"
FT /id="PRO_0000061834"
FT TRANSMEM 39..59
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 97..117
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 123..143
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 193..213
FT /note="Helical"
FT /evidence="ECO:0000255"
FT BINDING 42
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_label="1"
FT /note="covalent"
FT /evidence="ECO:0000250"
FT BINDING 93
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 /evidence="ECO:0000250"
FT BINDING 107
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 /evidence="ECO:0000250"
FT BINDING 194
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 /evidence="ECO:0000250"
FT BINDING 209
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 /evidence="ECO:0000250"
FT MUTAGEN 148
FT /note="D->G: Makes bacteria sensitive to myxothiazol."
FT /evidence="ECO:0000269|PubMed:11245788"
FT MUTAGEN 154
FT /note="A->G: Increases resistance to the quinone analog
FT DBMIB and to stigmatellin."
FT /evidence="ECO:0000269|PubMed:11245788"
FT MUTAGEN 159
FT /note="S->A: Increases resistance to the quinone analog
FT DBMIB."
FT /evidence="ECO:0000269|PubMed:11245788"
FT MUTAGEN 209
FT /note="H->Q: No assembly of cytochrome b6f complex."
FT /evidence="ECO:0000269|PubMed:11245788"
SQ SEQUENCE 222 AA; 25179 MW; 26EC3AAD95092F73 CRC64;
MFTKEVTDSK LYKWFNERLE IQAISDDISS KYVPPHVNIF YCLGGITLTC FIIQFATGFA
MTFYYKPTVA EAFTSVQYIM NEVNFGWLIR SIHRWSASMM VLMMILHIFR VYLTGGFKRP
RELTWITGVI MATITVSFGV TGYSLPWDQV GYWAVKIVSG VPAAIPVVGD QMVELLRGGA
SVGQATLTRF YSLHTFVLPW LIAVFMLAHF LMIRKQGISG PL
