ID   PETD_CYAM1              Reviewed;         160 AA.
AC   Q85G15;
DT   10-JAN-2006, integrated into UniProtKB/Swiss-Prot.
DT   01-JUN-2003, sequence version 1.
DT   03-AUG-2022, entry version 96.
DE   RecName: Full=Cytochrome b6-f complex subunit 4 {ECO:0000255|HAMAP-Rule:MF_01344};
DE   AltName: Full=17 kDa polypeptide {ECO:0000255|HAMAP-Rule:MF_01344};
GN   Name=petD {ECO:0000255|HAMAP-Rule:MF_01344};
OS   Cyanidioschyzon merolae (strain NIES-3377 / 10D) (Unicellular red alga).
OG   Plastid; Chloroplast.
OC   Eukaryota; Rhodophyta; Bangiophyceae; Cyanidiales; Cyanidiaceae;
OC   Cyanidioschyzon.
OX   NCBI_TaxID=280699;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=NIES-3377 / 10D;
RX   PubMed=12755171; DOI=10.1093/dnares/10.2.67;
RA   Ohta N., Matsuzaki M., Misumi O., Miyagishima S.-Y., Nozaki H., Tanaka K.,
RA   Shin-i T., Kohara Y., Kuroiwa T.;
RT   "Complete sequence and analysis of the plastid genome of the unicellular
RT   red alga Cyanidioschyzon merolae.";
RL   DNA Res. 10:67-77(2003).
CC   -!- FUNCTION: Component of the cytochrome b6-f complex, which mediates
CC       electron transfer between photosystem II (PSII) and photosystem I
CC       (PSI), cyclic electron flow around PSI, and state transitions.
CC       {ECO:0000255|HAMAP-Rule:MF_01344}.
CC   -!- SUBUNIT: The 4 large subunits of the cytochrome b6-f complex are
CC       cytochrome b6, subunit IV (17 kDa polypeptide, petD), cytochrome f and
CC       the Rieske protein, while the 4 small subunits are petG, petL, petM and
CC       petN. The complex functions as a dimer (By similarity). {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Plastid, chloroplast thylakoid membrane
CC       {ECO:0000255|HAMAP-Rule:MF_01344}; Multi-pass membrane protein
CC       {ECO:0000255|HAMAP-Rule:MF_01344}.
CC   -!- SIMILARITY: Belongs to the cytochrome b family. PetD subfamily.
CC       {ECO:0000255|HAMAP-Rule:MF_01344}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; AB002583; BAC76176.1; -; Genomic_DNA.
DR   RefSeq; NP_849014.1; NC_004799.1.
DR   AlphaFoldDB; Q85G15; -.
DR   SMR; Q85G15; -.
DR   STRING; 45157.CMV097CT; -.
DR   EnsemblPlants; CMV097CT; CMV097CT; CMV097C.
DR   GeneID; 844927; -.
DR   Gramene; CMV097CT; CMV097CT; CMV097C.
DR   KEGG; cme:CymeCp082; -.
DR   eggNOG; KOG4663; Eukaryota.
DR   HOGENOM; CLU_112652_0_0_1; -.
DR   Proteomes; UP000007014; Chloroplast.
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:0045158; F:electron transporter, transferring electrons within cytochrome b6/f complex of photosystem II activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0045156; F:electron transporter, transferring electrons within the cyclic electron transport pathway of photosynthesis activity; IEA:InterPro.
DR   GO; GO:0009767; P:photosynthetic electron transport chain; IEA:InterPro.
DR   CDD; cd00290; cytochrome_b_C; 1.
DR   HAMAP; MF_01344; Cytb6_f_subIV; 1.
DR   InterPro; IPR005798; Cyt_b/b6_C.
DR   InterPro; IPR036150; Cyt_b/b6_C_sf.
DR   InterPro; IPR005870; Cyt_b6/f_cplx_suIV.
DR   Pfam; PF00032; Cytochrom_B_C; 1.
DR   PIRSF; PIRSF000033; B6f_17K; 1.
DR   SUPFAM; SSF81648; SSF81648; 1.
DR   TIGRFAMs; TIGR01156; cytb6/f_IV; 1.
DR   PROSITE; PS51003; CYTB_CTER; 1.
PE   3: Inferred from homology;
KW   Chloroplast; Electron transport; Membrane; Photosynthesis; Plastid;
KW   Reference proteome; Thylakoid; Transmembrane; Transmembrane helix;
KW   Transport.
FT   CHAIN           1..160
FT                   /note="Cytochrome b6-f complex subunit 4"
FT                   /id="PRO_0000061857"
FT   TRANSMEM        36..56
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01344"
FT   TRANSMEM        95..115
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01344"
FT   TRANSMEM        127..147
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01344"
SQ   SEQUENCE   160 AA;  17648 MW;  C6863D4E8B46FF86 CRC64;
     MSILKKPDLS DAQLRAKLAK GMGHNMYGEP AWPNDLLYTF PVVILGTITC CIGLALMEPS
     AIGEAANPFA TPLEILPEWY FYPTFNLLRV IPNKLLGVLS MASVPLGLIF VPFIENRNRY
     QNPWRRPIAT TVFLVGTVVT IWLGIGATKS IQDAISLGLF