ID   PSBF_GRATL              Reviewed;          44 AA.
AC   Q6B8K5;
DT   15-MAR-2005, integrated into UniProtKB/Swiss-Prot.
DT   13-SEP-2004, sequence version 1.
DT   03-AUG-2022, entry version 70.
DE   RecName: Full=Cytochrome b559 subunit beta {ECO:0000255|HAMAP-Rule:MF_00643};
DE   AltName: Full=PSII reaction center subunit VI {ECO:0000255|HAMAP-Rule:MF_00643};
GN   Name=psbF {ECO:0000255|HAMAP-Rule:MF_00643}; OrderedLocusNames=Grc000199;
OS   Gracilaria tenuistipitata var. liui (Red alga).
OG   Plastid; Chloroplast.
OC   Eukaryota; Rhodophyta; Florideophyceae; Rhodymeniophycidae; Gracilariales;
OC   Gracilariaceae; Agarophyton; Agarophyton tenuistipitatum.
OX   NCBI_TaxID=285951;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RX   PubMed=15638458; DOI=10.1007/s00239-004-2638-3;
RA   Hagopian J.C., Reis M., Kitajima J.P., Bhattacharya D., de Oliveira M.C.;
RT   "Comparative analysis of the complete plastid genome sequence of the red
RT   alga Gracilaria tenuistipitata var. liui provides insights into the
RT   evolution of rhodoplasts and their relationship to other plastids.";
RL   J. Mol. Evol. 59:464-477(2004).
CC   -!- FUNCTION: This b-type cytochrome is tightly associated with the
CC       reaction center of photosystem II (PSII). PSII is a light-driven
CC       water:plastoquinone oxidoreductase that uses light energy to abstract
CC       electrons from H(2)O, generating O(2) and a proton gradient
CC       subsequently used for ATP formation. It consists of a core antenna
CC       complex that captures photons, and an electron transfer chain that
CC       converts photonic excitation into a charge separation.
CC       {ECO:0000255|HAMAP-Rule:MF_00643}.
CC   -!- COFACTOR:
CC       Name=heme b; Xref=ChEBI:CHEBI:60344;
CC         Evidence={ECO:0000255|HAMAP-Rule:MF_00643};
CC       Note=With its partner (PsbE) binds heme. PSII binds additional
CC       chlorophylls, carotenoids and specific lipids. {ECO:0000255|HAMAP-
CC       Rule:MF_00643};
CC   -!- SUBUNIT: Heterodimer of an alpha subunit and a beta subunit. PSII is
CC       composed of 1 copy each of membrane proteins PsbA, PsbB, PsbC, PsbD,
CC       PsbE, PsbF, PsbH, PsbI, PsbJ, PsbK, PsbL, PsbM, PsbT, PsbX, PsbY, PsbZ,
CC       Ycf12, at least 3 peripheral proteins of the oxygen-evolving complex
CC       and a large number of cofactors. It forms dimeric complexes.
CC       {ECO:0000255|HAMAP-Rule:MF_00643}.
CC   -!- SUBCELLULAR LOCATION: Plastid, chloroplast thylakoid membrane
CC       {ECO:0000255|HAMAP-Rule:MF_00643}; Single-pass membrane protein
CC       {ECO:0000255|HAMAP-Rule:MF_00643}.
CC   -!- SIMILARITY: Belongs to the PsbE/PsbF family. {ECO:0000255|HAMAP-
CC       Rule:MF_00643}.
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DR   EMBL; AY673996; AAT79780.1; -; Genomic_DNA.
DR   RefSeq; YP_063705.1; NC_006137.1.
DR   AlphaFoldDB; Q6B8K5; -.
DR   GeneID; 2943978; -.
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:0009539; C:photosystem II reaction center; IEA:InterPro.
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:UniProtKB-UniRule.
DR   GO; GO:0009767; P:photosynthetic electron transport chain; IEA:InterPro.
DR   HAMAP; MF_00643; PSII_PsbF; 1.
DR   InterPro; IPR006241; PSII_cyt_b559_bsu.
DR   InterPro; IPR006216; PSII_cyt_b559_CS.
DR   InterPro; IPR013081; PSII_cyt_b559_N.
DR   PANTHER; PTHR33391:SF14; PTHR33391:SF14; 1.
DR   Pfam; PF00283; Cytochrom_B559; 1.
DR   PIRSF; PIRSF000037; PsbF; 1.
DR   TIGRFAMs; TIGR01333; cyt_b559_beta; 1.
DR   PROSITE; PS00537; CYTOCHROME_B559; 1.
PE   3: Inferred from homology;
KW   Chloroplast; Electron transport; Heme; Iron; Membrane; Metal-binding;
KW   Photosynthesis; Photosystem II; Plastid; Thylakoid; Transmembrane;
KW   Transmembrane helix; Transport.
FT   CHAIN           1..44
FT                   /note="Cytochrome b559 subunit beta"
FT                   /id="PRO_0000200394"
FT   TRANSMEM        19..35
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00643"
FT   BINDING         23
FT                   /ligand="heme"
FT                   /ligand_id="ChEBI:CHEBI:30413"
FT                   /ligand_note="ligand shared with alpha subunit"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00643"
SQ   SEQUENCE   44 AA;  5043 MW;  F9C708E024DAA8DD CRC64;
     MTRGNSNQPI SYPIFTFRWL AIHGIAIPTV FFLGAITSMQ FIQR