ID   PSBF_MESVI              Reviewed;          41 AA.
AC   Q9MUQ1;
DT   27-APR-2001, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-2000, sequence version 1.
DT   03-AUG-2022, entry version 85.
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};
OS   Mesostigma viride (Green alga).
OG   Plastid; Chloroplast.
OC   Eukaryota; Viridiplantae; Streptophyta; Mesostigmatophyceae;
OC   Mesostigmatales; Mesostigmataceae; Mesostigma.
OX   NCBI_TaxID=41882;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=NIES-296 / KY-14 / CCMP 2046;
RX   PubMed=10688199; DOI=10.1038/35001059;
RA   Lemieux C., Otis C., Turmel M.;
RT   "Ancestral chloroplast genome in Mesostigma viride reveals an early branch
RT   of green plant evolution.";
RL   Nature 403:649-652(2000).
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; AF166114; AAF43849.1; -; Genomic_DNA.
DR   RefSeq; NP_038409.1; NC_002186.1.
DR   AlphaFoldDB; Q9MUQ1; -.
DR   GeneID; 800917; -.
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..41
FT                   /note="Cytochrome b559 subunit beta"
FT                   /id="PRO_0000200420"
FT   TRANSMEM        16..32
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00643"
FT   BINDING         20
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   41 AA;  4654 MW;  F402F052BA03183F CRC64;
     MAAEKTIQYP IFTVRWLSVH ALAVPTVFFL GAISAMQFIQ R