ID   PSBF_NOSS1              Reviewed;          45 AA.
AC   Q8YQI1;
DT   30-MAY-2003, integrated into UniProtKB/Swiss-Prot.
DT   01-MAR-2002, sequence version 1.
DT   03-AUG-2022, entry version 106.
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=asr3846;
OS   Nostoc sp. (strain PCC 7120 / SAG 25.82 / UTEX 2576).
OC   Bacteria; Cyanobacteria; Nostocales; Nostocaceae; Nostoc.
OX   NCBI_TaxID=103690;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=PCC 7120 / SAG 25.82 / UTEX 2576;
RX   PubMed=11759840; DOI=10.1093/dnares/8.5.205;
RA   Kaneko T., Nakamura Y., Wolk C.P., Kuritz T., Sasamoto S., Watanabe A.,
RA   Iriguchi M., Ishikawa A., Kawashima K., Kimura T., Kishida Y., Kohara M.,
RA   Matsumoto M., Matsuno A., Muraki A., Nakazaki N., Shimpo S., Sugimoto M.,
RA   Takazawa M., Yamada M., Yasuda M., Tabata S.;
RT   "Complete genomic sequence of the filamentous nitrogen-fixing
RT   cyanobacterium Anabaena sp. strain PCC 7120.";
RL   DNA Res. 8:205-213(2001).
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.
CC       Cyanobacterial PSII is composed of 1 copy each of membrane proteins
CC       PsbA, PsbB, PsbC, PsbD, PsbE, PsbF, PsbH, PsbI, PsbJ, PsbK, PsbL, PsbM,
CC       PsbT, PsbX, PsbY, PsbZ, Ycf12, at least 3 peripheral proteins PsbO,
CC       PsbU, PsbV and a large number of cofactors. It forms dimeric complexes.
CC       {ECO:0000255|HAMAP-Rule:MF_00643}.
CC   -!- SUBCELLULAR LOCATION: Cellular thylakoid membrane {ECO:0000255|HAMAP-
CC       Rule:MF_00643}; Single-pass membrane protein {ECO:0000255|HAMAP-
CC       Rule:MF_00643}.
CC   -!- SIMILARITY: Belongs to the PsbE/PsbF family. {ECO:0000255|HAMAP-
CC       Rule:MF_00643}.
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DR   EMBL; BA000019; BAB75545.1; -; Genomic_DNA.
DR   PIR; AG2286; AG2286.
DR   RefSeq; WP_010997987.1; NZ_RSCN01000011.1.
DR   AlphaFoldDB; Q8YQI1; -.
DR   STRING; 103690.17132980; -.
DR   EnsemblBacteria; BAB75545; BAB75545; BAB75545.
DR   KEGG; ana:asr3846; -.
DR   eggNOG; ENOG50332KX; Bacteria.
DR   Proteomes; UP000002483; Chromosome.
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:0031676; C:plasma membrane-derived thylakoid membrane; 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: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   Electron transport; Heme; Iron; Membrane; Metal-binding; Photosynthesis;
KW   Photosystem II; Reference proteome; Thylakoid; Transmembrane;
KW   Transmembrane helix; Transport.
FT   CHAIN           1..45
FT                   /note="Cytochrome b559 subunit beta"
FT                   /id="PRO_0000200467"
FT   TRANSMEM        20..36
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00643"
FT   BINDING         24
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   45 AA;  5052 MW;  7A9D18CFF8A8EBBB CRC64;
     MTSGNNINQP VTYPIFTVRW IAVHTLAVPT VFFLGAIASM QFIQR