ID   CYC6_LIMMA              Reviewed;          89 AA.
AC   P00118;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   21-JUL-1986, sequence version 1.
DT   03-AUG-2022, entry version 119.
DE   RecName: Full=Cytochrome c6;
DE   AltName: Full=Cytochrome c-553;
DE   AltName: Full=Cytochrome c553;
DE   AltName: Full=Soluble cytochrome f {ECO:0000303|PubMed:803642};
GN   Name=petJ;
OS   Limnospira maxima (Arthrospira maxima).
OC   Bacteria; Cyanobacteria; Oscillatoriophycideae; Oscillatoriales;
OC   Sirenicapillariaceae; Limnospira.
OX   NCBI_TaxID=129910;
RN   [1]
RP   PROTEIN SEQUENCE.
RX   PubMed=803642; DOI=10.1038/253285a0;
RA   Ambler R.P., Bartsch R.G.;
RT   "Amino acid sequence similarity between cytochrome f from a blue-green
RT   bacterium and algal chloroplasts.";
RL   Nature 253:285-288(1975).
RN   [2]
RP   X-RAY CRYSTALLOGRAPHY (2.7 ANGSTROMS) IN COMPLEX WITH HEME, COFACTOR, AND
RP   SUBUNIT.
RX   PubMed=11478889; DOI=10.1021/bi002679p;
RA   Sawaya M.R., Krogmann D.W., Serag A., Ho K.K., Yeates T.O., Kerfeld C.A.;
RT   "Structures of cytochrome c-549 and cytochrome c6 from the cyanobacterium
RT   Arthrospira maxima.";
RL   Biochemistry 40:9215-9225(2001).
RN   [3]
RP   X-RAY CRYSTALLOGRAPHY (3.5 ANGSTROMS) IN COMPLEX WITH HEME, COFACTOR, AND
RP   SUBUNIT.
RX   PubMed=12077429; DOI=10.1107/s0907444902006534;
RA   Kerfeld C.A., Sawaya M.R., Krogmann D.W., Yeates T.O.;
RT   "Structure of cytochrome c6 from Arthrospira maxima: an assembly of 24
RT   subunits in a nearly symmetric shell.";
RL   Acta Crystallogr. D 58:1104-1110(2002).
CC   -!- FUNCTION: Functions as an electron carrier between membrane-bound
CC       cytochrome b6-f and photosystem I in oxygenic photosynthesis.
CC       {ECO:0000305}.
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       Redox potential:
CC         E(0) is +314 mV.;
CC   -!- SUBUNIT: Monomer. Homodimer, or even higher oligomerization, in crystal
CC       structures (PubMed:11478889, PubMed:12077429).
CC       {ECO:0000269|PubMed:11478889, ECO:0000269|PubMed:12077429}.
CC   -!- SUBCELLULAR LOCATION: Cellular thylakoid lumen {ECO:0000305}.
CC   -!- PTM: Binds 1 heme c group covalently per subunit.
CC       {ECO:0000269|PubMed:11478889, ECO:0000269|PubMed:12077429}.
CC   -!- SIMILARITY: Belongs to the cytochrome c family. PetJ subfamily.
CC       {ECO:0000305}.
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DR   PIR; A00110; CCSG6.
DR   PDB; 1F1F; X-ray; 2.70 A; A=1-89.
DR   PDB; 1KIB; X-ray; 3.50 A; A/B/C/D/E/F/G/H=1-89.
DR   PDBsum; 1F1F; -.
DR   PDBsum; 1KIB; -.
DR   AlphaFoldDB; P00118; -.
DR   SMR; P00118; -.
DR   EvolutionaryTrace; P00118; -.
DR   GO; GO:0031979; C:plasma membrane-derived thylakoid lumen; IEA:UniProtKB-SubCell.
DR   GO; GO:0009055; F:electron transfer activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0020037; F:heme binding; IEA:InterPro.
DR   GO; GO:0005506; F:iron ion binding; IEA:InterPro.
DR   GO; GO:0015979; P:photosynthesis; IEA:UniProtKB-UniRule.
DR   Gene3D; 1.10.760.10; -; 1.
DR   HAMAP; MF_00594; Cytc_PetJ; 1.
DR   InterPro; IPR009056; Cyt_c-like_dom.
DR   InterPro; IPR036909; Cyt_c-like_dom_sf.
DR   InterPro; IPR023655; Cyt_C6.
DR   InterPro; IPR008168; Cyt_C_IC.
DR   PANTHER; PTHR34688; PTHR34688; 1.
DR   Pfam; PF13442; Cytochrome_CBB3; 1.
DR   PRINTS; PR00605; CYTCHROMECIC.
DR   SUPFAM; SSF46626; SSF46626; 1.
DR   PROSITE; PS51007; CYTC; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Direct protein sequencing; Electron transport; Heme; Iron;
KW   Metal-binding; Photosynthesis; Thylakoid; Transport.
FT   CHAIN           1..89
FT                   /note="Cytochrome c6"
FT                   /id="PRO_0000208686"
FT   BINDING         14
FT                   /ligand="heme c"
FT                   /ligand_id="ChEBI:CHEBI:61717"
FT                   /note="covalent"
FT                   /evidence="ECO:0000269|PubMed:11478889,
FT                   ECO:0000269|PubMed:12077429"
FT   BINDING         17
FT                   /ligand="heme c"
FT                   /ligand_id="ChEBI:CHEBI:61717"
FT                   /note="covalent"
FT                   /evidence="ECO:0000269|PubMed:11478889,
FT                   ECO:0000269|PubMed:12077429"
FT   BINDING         18
FT                   /ligand="heme c"
FT                   /ligand_id="ChEBI:CHEBI:61717"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT                   /evidence="ECO:0000269|PubMed:11478889,
FT                   ECO:0000269|PubMed:12077429"
FT   BINDING         62
FT                   /ligand="heme c"
FT                   /ligand_id="ChEBI:CHEBI:61717"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT                   /evidence="ECO:0000269|PubMed:11478889,
FT                   ECO:0000269|PubMed:12077429"
FT   HELIX           3..13
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   HELIX           15..18
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   HELIX           19..21
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   STRAND          24..26
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   HELIX           33..39
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   TURN            41..45
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   HELIX           47..57
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   TURN            66..68
FT                   /evidence="ECO:0007829|PDB:1F1F"
FT   HELIX           71..87
FT                   /evidence="ECO:0007829|PDB:1F1F"
SQ   SEQUENCE   89 AA;  9236 MW;  4796D56B3EA8AF85 CRC64;
     GDVAAGASVF SANCAACHMG GRNVIVANKT LSKSDLAKYL KGFDDDAVAA VAYQVTNGKN
     AMPGFNGRLS PKQIEDVAAY VVDQAEKGW