PSAB_PROM3
ID PSAB_PROM3 Reviewed; 749 AA.
AC A2CC72;
DT 11-SEP-2007, integrated into UniProtKB/Swiss-Prot.
DT 20-FEB-2007, sequence version 1.
DT 03-AUG-2022, entry version 89.
DE RecName: Full=Photosystem I P700 chlorophyll a apoprotein A2 {ECO:0000255|HAMAP-Rule:MF_00482};
DE EC=1.97.1.12 {ECO:0000255|HAMAP-Rule:MF_00482};
DE AltName: Full=PsaB {ECO:0000255|HAMAP-Rule:MF_00482};
GN Name=psaB {ECO:0000255|HAMAP-Rule:MF_00482}; OrderedLocusNames=P9303_23471;
OS Prochlorococcus marinus (strain MIT 9303).
OC Bacteria; Cyanobacteria; Synechococcales; Prochlorococcaceae;
OC Prochlorococcus.
OX NCBI_TaxID=59922;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=MIT 9303;
RX PubMed=18159947; DOI=10.1371/journal.pgen.0030231;
RA Kettler G.C., Martiny A.C., Huang K., Zucker J., Coleman M.L., Rodrigue S.,
RA Chen F., Lapidus A., Ferriera S., Johnson J., Steglich C., Church G.M.,
RA Richardson P., Chisholm S.W.;
RT "Patterns and implications of gene gain and loss in the evolution of
RT Prochlorococcus.";
RL PLoS Genet. 3:2515-2528(2007).
CC -!- FUNCTION: PsaA and PsaB bind P700, the primary electron donor of
CC photosystem I (PSI), as well as the electron acceptors A0, A1 and FX.
CC PSI is a plastocyanin/cytochrome c6-ferredoxin oxidoreductase,
CC converting photonic excitation into a charge separation, which
CC transfers an electron from the donor P700 chlorophyll pair to the
CC spectroscopically characterized acceptors A0, A1, FX, FA and FB in
CC turn. Oxidized P700 is reduced on the lumenal side of the thylakoid
CC membrane by plastocyanin or cytochrome c6. {ECO:0000255|HAMAP-
CC Rule:MF_00482}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=hnu + oxidized [2Fe-2S]-[ferredoxin] + reduced [plastocyanin]
CC = oxidized [plastocyanin] + reduced [2Fe-2S]-[ferredoxin];
CC Xref=Rhea:RHEA:30407, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001,
CC Rhea:RHEA-COMP:10039, Rhea:RHEA-COMP:10040, ChEBI:CHEBI:29036,
CC ChEBI:CHEBI:30212, ChEBI:CHEBI:33737, ChEBI:CHEBI:33738,
CC ChEBI:CHEBI:49552; EC=1.97.1.12; Evidence={ECO:0000255|HAMAP-
CC Rule:MF_00482};
CC -!- COFACTOR:
CC Note=PSI electron transfer chain: 5 divinyl chlorophyll a, 1 divinyl
CC chlorophyll a', 2 phylloquinones and 3 4Fe-4S clusters. PSI core
CC antenna: 90 divinyl chlorophyll a, 22 carotenoids, 3 phospholipids and
CC 1 galactolipid. P700 is a divinyl chlorophyll a/divinyl chlorophyll a'
CC dimer, A0 is one or more divinyl chlorophyll a, A1 is one or both
CC phylloquinones and FX is a shared 4Fe-4S iron-sulfur center.
CC {ECO:0000255|HAMAP-Rule:MF_00482};
CC -!- SUBUNIT: The PsaA/B heterodimer binds the P700 divinyl chlorophyll
CC special pair and subsequent electron acceptors. PSI consists of a core
CC antenna complex that captures photons, and an electron transfer chain
CC that converts photonic excitation into a charge separation. The
CC cyanobacterial PSI reaction center is composed of one copy each of
CC PsaA,B,C,D,E,F,I,J,K,L,M and X, and forms trimeric complexes.
CC {ECO:0000255|HAMAP-Rule:MF_00482}.
CC -!- SUBCELLULAR LOCATION: Cellular thylakoid membrane {ECO:0000255|HAMAP-
CC Rule:MF_00482}; Multi-pass membrane protein {ECO:0000255|HAMAP-
CC Rule:MF_00482}.
CC -!- SIMILARITY: Belongs to the PsaA/PsaB family. {ECO:0000255|HAMAP-
CC Rule:MF_00482}.
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DR EMBL; CP000554; ABM79082.1; -; Genomic_DNA.
DR AlphaFoldDB; A2CC72; -.
DR SMR; A2CC72; -.
DR STRING; 59922.P9303_23471; -.
DR EnsemblBacteria; ABM79082; ABM79082; P9303_23471.
DR KEGG; pmf:P9303_23471; -.
DR HOGENOM; CLU_016126_1_0_3; -.
DR OMA; FEQWVAD; -.
DR BioCyc; PMAR59922:G1G80-2064-MON; -.
DR Proteomes; UP000002274; Chromosome.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0009522; C:photosystem I; IEA:UniProtKB-KW.
DR GO; GO:0031676; C:plasma membrane-derived thylakoid membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0051539; F:4 iron, 4 sulfur cluster binding; IEA:UniProtKB-KW.
DR GO; GO:0016168; F:chlorophyll binding; IEA:UniProtKB-KW.
DR GO; GO:0009055; F:electron transfer activity; IEA:UniProtKB-UniRule.
DR GO; GO:0000287; F:magnesium ion binding; IEA:UniProtKB-UniRule.
DR GO; GO:0015979; P:photosynthesis; IEA:UniProtKB-UniRule.
DR Gene3D; 1.20.1130.10; -; 1.
DR HAMAP; MF_00482; PSI_PsaB; 1.
DR InterPro; IPR001280; PSI_PsaA/B.
DR InterPro; IPR020586; PSI_PsaA/B_CS.
DR InterPro; IPR036408; PSI_PsaA/B_sf.
DR InterPro; IPR006244; PSI_PsaB.
DR Pfam; PF00223; PsaA_PsaB; 1.
DR PIRSF; PIRSF002905; PSI_A; 1.
DR PRINTS; PR00257; PHOTSYSPSAAB.
DR SUPFAM; SSF81558; SSF81558; 1.
DR TIGRFAMs; TIGR01336; psaB; 1.
DR PROSITE; PS00419; PHOTOSYSTEM_I_PSAAB; 1.
PE 3: Inferred from homology;
KW 4Fe-4S; Chlorophyll; Chromophore; Electron transport; Iron; Iron-sulfur;
KW Magnesium; Membrane; Metal-binding; Oxidoreductase; Photosynthesis;
KW Photosystem I; Thylakoid; Transmembrane; Transmembrane helix; Transport.
FT CHAIN 1..749
FT /note="Photosystem I P700 chlorophyll a apoprotein A2"
FT /id="PRO_0000300018"
FT TRANSMEM 46..69
FT /note="Helical; Name=I"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 135..158
FT /note="Helical; Name=II"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 175..199
FT /note="Helical; Name=III"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 273..291
FT /note="Helical; Name=IV"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 343..366
FT /note="Helical; Name=V"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 382..408
FT /note="Helical; Name=VI"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 430..452
FT /note="Helical; Name=VII"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 532..550
FT /note="Helical; Name=VIII"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 590..611
FT /note="Helical; Name=IX"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 658..680
FT /note="Helical; Name=X"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 722..742
FT /note="Helical; Name=XI"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 574
FT /ligand="[4Fe-4S] cluster"
FT /ligand_id="ChEBI:CHEBI:49883"
FT /ligand_note="ligand shared between dimeric partners"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 583
FT /ligand="[4Fe-4S] cluster"
FT /ligand_id="ChEBI:CHEBI:49883"
FT /ligand_note="ligand shared between dimeric partners"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 669
FT /ligand="divinyl chlorophyll a"
FT /ligand_id="ChEBI:CHEBI:73095"
FT /ligand_label="B1"
FT /ligand_part="Mg"
FT /ligand_part_id="ChEBI:CHEBI:25107"
FT /note="axial binding residue"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 677
FT /ligand="divinyl chlorophyll a"
FT /ligand_id="ChEBI:CHEBI:73095"
FT /ligand_label="B3"
FT /ligand_part="Mg"
FT /ligand_part_id="ChEBI:CHEBI:25107"
FT /note="axial binding residue"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 685
FT /ligand="divinyl chlorophyll a"
FT /ligand_id="ChEBI:CHEBI:73095"
FT /ligand_label="B3"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 686
FT /ligand="phylloquinone"
FT /ligand_id="ChEBI:CHEBI:18067"
FT /ligand_label="B"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
SQ SEQUENCE 749 AA; 83151 MW; 6C0AE61033501E0C CRC64;
MATKFPSFSQ GLAQDPTTRR IWYGIATAHD FESHDGMTEE RLYQKLFSTH FGHLAVIGLW
VAGNLFHIAW QGNFEQWVAD PQNVQPIAHA IWDPHFGQGI SDALTQAGAS RPVNICYSGL
YHWWYTIGMR TNTELYQGAI FIDILVAWLL FGGWLHLQPK FRPSLAWFKN AEAMMNHHLA
VLFGFTNIAW TGHLVHVAIP ESRGQHVGWD NFLTVLPHPE GLTPFFTGNW GAYAQNPDSL
NHAFGTSEGA GTAILTFLGG VHPQSGALWL TDISHHHIAI GVFMIIGGHM YRNSFGIGHT
FKEITDGHNT SHPNDPHKDG FREKIGHYGL SHTGITDTIN NSLHFQLGLA LACLGTAASL
VAHHMGALPS YAFIAQDYTT QAALYTHHQY IAIFLMCGAF SHGAIFFVRD YDPEANKDNV
LARVLETKEA LISHLSWVCM LLGFHTLALY LHNDVVIAFG TPEKQILVEP IFAQFIQAAS
GKVMYGLDVL LANANSAPSL AAAGMPGDHY WMDLINASPE VSNFMPIGPG DFLVHHGIAL
GLHTTALILI KGALDARGSK LMPDKKDFGY AFACDGPGRG GTCDISAWDS TYMAIFWALN
TIAWATYYWH WKHLAAWQGN MAQFNESSTH LMGWFRDYLW INSSQIINGY NPFGINNLSP
WAYMFLAGHL VWATGFMFLI SWRGYWQELI ETLVWAHQRS PIANLVGWRD KPVALSIVQA
RLVGVTHFAV GNIFTFGAFV IASTASKFG
