ID   CY550_APHFL             Reviewed;         119 AA.
AC   P56151;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1997, sequence version 1.
DT   03-AUG-2022, entry version 80.
DE   RecName: Full=Cytochrome c-550;
DE   AltName: Full=Cytochrome c550;
DE   AltName: Full=Low-potential cytochrome c;
DE   Flags: Fragment;
GN   Name=psbV;
OS   Aphanizomenon flos-aquae.
OC   Bacteria; Cyanobacteria; Nostocales; Aphanizomenonaceae; Aphanizomenon.
OX   NCBI_TaxID=1176;
RN   [1]
RP   PROTEIN SEQUENCE.
RX   PubMed=2539046; DOI=10.1016/0003-9861(89)90024-6;
RA   Cohn C.L., Sprinkle J.R., Alam J., Hermodson M., Meyer T., Krogmann D.W.;
RT   "The amino acid sequence of low-potential cytochrome c550 from the
RT   cyanobacterium Microcystis aeruginosa.";
RL   Arch. Biochem. Biophys. 270:227-235(1989).
CC   -!- FUNCTION: Low-potential cytochrome c that plays a role in the oxygen-
CC       evolving complex of photosystem II. {ECO:0000250}.
CC   -!- COFACTOR:
CC       Name=heme c; Xref=ChEBI:CHEBI:61717;
CC       Note=Binds 1 heme c group covalently per subunit.;
CC   -!- SUBUNIT: The cyanobacterial oxygen-evolving complex is composed of
CC       PsbO, PsbP, PsbQ, PsbV and PsbU. {ECO:0000305}.
CC   -!- SUBCELLULAR LOCATION: Cellular thylakoid membrane {ECO:0000250};
CC       Peripheral membrane protein {ECO:0000250}; Lumenal side {ECO:0000250}.
CC       Note=Associated with photosystem II at the lumenal side of the
CC       thylakoid membrane. {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the cytochrome c family. PsbV subfamily.
CC       {ECO:0000305}.
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DR   PIR; S07476; S07476.
DR   AlphaFoldDB; P56151; -.
DR   SMR; P56151; -.
DR   GO; GO:0009523; C:photosystem II; IEA:UniProtKB-KW.
DR   GO; GO:0031676; C:plasma membrane-derived thylakoid membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0009055; F:electron transfer activity; IEA:InterPro.
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-KW.
DR   GO; GO:0022904; P:respiratory electron transport chain; IEA:InterPro.
DR   Gene3D; 1.10.760.10; -; 1.
DR   InterPro; IPR009056; Cyt_c-like_dom.
DR   InterPro; IPR036909; Cyt_c-like_dom_sf.
DR   InterPro; IPR029490; Cytochrom_C550.
DR   InterPro; IPR016003; PSII_cyt_c550.
DR   Pfam; PF14495; Cytochrom_C550; 1.
DR   PIRSF; PIRSF005890; Phot_II_cyt_c550; 1.
DR   SUPFAM; SSF46626; SSF46626; 1.
DR   PROSITE; PS51007; CYTC; 1.
PE   1: Evidence at protein level;
KW   Direct protein sequencing; Electron transport; Heme; Iron; Membrane;
KW   Metal-binding; Photosynthesis; Photosystem II; Thylakoid; Transport.
FT   CHAIN           1..>119
FT                   /note="Cytochrome c-550"
FT                   /id="PRO_0000108382"
FT   BINDING         36
FT                   /ligand="heme c"
FT                   /ligand_id="ChEBI:CHEBI:61717"
FT                   /note="covalent"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00433"
FT   BINDING         39
FT                   /ligand="heme c"
FT                   /ligand_id="ChEBI:CHEBI:61717"
FT                   /note="covalent"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00433"
FT   BINDING         40
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:0000255|PROSITE-ProRule:PRU00433"
FT   NON_TER         119
SQ   SEQUENCE   119 AA;  12888 MW;  D30E2CD3CDADCAA1 CRC64;
     LELDETIRTV PLNDKGGTVV LSLEQVKEGK LFNYACAQCH AGGVTKTNQN VGLEPEALAG
     ALPNRMKNPT TYDGEEEISE IPSIKSANIF RNLTDEDLKA IAEHILLEPL VVGTKWGGK