PSAB_CHAGL
ID PSAB_CHAGL Reviewed; 734 AA.
AC Q8M9V9;
DT 08-NOV-2002, integrated into UniProtKB/Swiss-Prot.
DT 01-OCT-2002, sequence version 1.
DT 03-AUG-2022, entry version 86.
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=PSI-B {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};
OS Chaetosphaeridium globosum (Charophycean green alga) (Herposteiron
OS globosum).
OG Plastid; Chloroplast.
OC Eukaryota; Viridiplantae; Streptophyta; Coleochaetophyceae; Coleochaetales;
OC Chaetosphaeridiaceae; Chaetosphaeridium.
OX NCBI_TaxID=96477;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=M1311;
RX PubMed=12161560; DOI=10.1073/pnas.162203299;
RA Turmel M., Otis C., Lemieux C.;
RT "The chloroplast and mitochondrial genome sequences of the charophyte
RT Chaetosphaeridium globosum: insights into the timing of the events that
RT restructured organelle DNAs within the green algal lineage that led to land
RT plants.";
RL Proc. Natl. Acad. Sci. U.S.A. 99:11275-11280(2002).
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-ferredoxin oxidoreductase, converting photonic
CC excitation into a charge separation, which transfers an electron from
CC the donor P700 chlorophyll pair to the spectroscopically characterized
CC acceptors A0, A1, FX, FA and FB in turn. Oxidized P700 is reduced on
CC the lumenal side of the thylakoid membrane by plastocyanin.
CC {ECO:0000255|HAMAP-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=P700 is a chlorophyll a/chlorophyll a' dimer, A0 is one or more
CC chlorophyll a, A1 is one or both phylloquinones and FX is a shared 4Fe-
CC 4S iron-sulfur center. {ECO:0000255|HAMAP-Rule:MF_00482};
CC -!- SUBUNIT: The PsaA/B heterodimer binds the P700 chlorophyll special pair
CC and subsequent electron acceptors. PSI consists of a core antenna
CC complex that captures photons, and an electron transfer chain that
CC converts photonic excitation into a charge separation. The eukaryotic
CC PSI reaction center is composed of at least 11 subunits.
CC {ECO:0000255|HAMAP-Rule:MF_00482}.
CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast thylakoid membrane
CC {ECO:0000255|HAMAP-Rule:MF_00482}; Multi-pass membrane protein
CC {ECO:0000255|HAMAP-Rule:MF_00482}.
CC -!- SIMILARITY: Belongs to the PsaA/PsaB family. {ECO:0000255|HAMAP-
CC Rule:MF_00482}.
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DR EMBL; AF494278; AAM96533.1; -; Genomic_DNA.
DR RefSeq; NP_683830.1; NC_004115.1.
DR AlphaFoldDB; Q8M9V9; -.
DR SMR; Q8M9V9; -.
DR GeneID; 860689; -.
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:0009522; C:photosystem I; IEA:UniProtKB-KW.
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; Chloroplast; Chromophore; Electron transport; Iron;
KW Iron-sulfur; Magnesium; Membrane; Metal-binding; Oxidoreductase;
KW Photosynthesis; Photosystem I; Plastid; Thylakoid; Transmembrane;
KW Transmembrane helix; Transport.
FT CHAIN 1..734
FT /note="Photosystem I P700 chlorophyll a apoprotein A2"
FT /id="PRO_0000088607"
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 330..353
FT /note="Helical; Name=V"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 369..395
FT /note="Helical; Name=VI"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 417..439
FT /note="Helical; Name=VII"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 517..535
FT /note="Helical; Name=VIII"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 575..596
FT /note="Helical; Name=IX"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 643..665
FT /note="Helical; Name=X"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT TRANSMEM 707..727
FT /note="Helical; Name=XI"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 559
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 568
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 654
FT /ligand="chlorophyll a"
FT /ligand_id="ChEBI:CHEBI:58416"
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 662
FT /ligand="chlorophyll a"
FT /ligand_id="ChEBI:CHEBI:58416"
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 670
FT /ligand="chlorophyll a"
FT /ligand_id="ChEBI:CHEBI:58416"
FT /ligand_label="B3"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
FT BINDING 671
FT /ligand="phylloquinone"
FT /ligand_id="ChEBI:CHEBI:18067"
FT /ligand_label="B"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00482"
SQ SEQUENCE 734 AA; 81925 MW; 4F39D1E66489A11B CRC64;
MASRFPKFSQ GLSQDPTTRR IWFGIATAHD FESHDGITEE KLYQKIFASH FGQLAVIFLW
TSGNLFHVAW QGNFEAWSQD PLHVRPIAHA IWDPHFGQPA VEAFTRGGAS GPVNISYSGV
YQWWYTQGIR TNLELYQGAL FLLGLAAVSL AAGWLHLQPK WQPKISWFKN AESRLNHHLS
GLFGVSSLAW SGHLVHVAIP ESRGQHVGWD NLLTTLPHPA GLAPFFSGQW SVYSQNPDSA
SHLFSTSQGS GTAILTFLGG FHPQTQSLWL TDIAHHHLAI AVLFIIAGHQ YRTNFGIGHS
IREILESHVP PGGGLGQGHK GLYDTLNNSL HFQLGLALAS LGVITSLVAQ HMYSLPSYAF
IAQDFTTQAA LYTHHQYIAG FIMSGAFAHG AIFFIRDYNP EQNKGNVLAR MLEHKEAIIS
HLSWASLFLG FHTLGLYVHN DVVQAFGNPE KQILIEPVFA QWIQSSHGKT LYGFDVFLSS
TASPAFYAGQ SLWLPGWLDS INSNTNSLFL TIGPGDFLVH HAIALGLHTT TLILVKGALD
ARGSKLMPDK KEFGYSFPCD GPGRGGTCDI SAWDAFYLAI FWMLNTIGWV TFYWHWKHLA
LWQGNAAQFN ESSTYLMGWL RDYLWLNSSQ LINGYNPFGM NSLSVWAWMF LFGHLIWATG
FMFLISWRGY WQELIETLAW AHERTPLANL VRWKDKPVAL SIVQARLVGL AHFSVGYIFT
YAAFLIASTS GKFG
