A0A8J6R5D0 · A0A8J6R5D0_9CYAN

  • Protein
    Photosystem I P700 chlorophyll a apoprotein A2
  • Gene
    psaB
  • Status
    UniProtKB unreviewed (TrEMBL)
  • Amino acids
  • Protein existence
    Inferred from homology
  • Annotation score
    3/5

Function

function

PsaA and PsaB bind P700, the primary electron donor of photosystem I (PSI), as well as the electron acceptors A0, A1 and FX. PSI is a plastocyanin/cytochrome c6-ferredoxin oxidoreductase, converting photonic excitation into a charge separation, which transfers an electron from the donor P700 chlorophyll pair to the spectroscopically characterized acceptors A0, A1, FX, FA and FB in turn. Oxidized P700 is reduced on the lumenal side of the thylakoid membrane by plastocyanin or cytochrome c6.
PsaA and psaB bind P700, the primary electron donor of photosystem I (PSI), as well as the electron acceptors A0, A1 and FX.

Caution

The sequence shown here is derived from an EMBL/GenBank/DDBJ whole genome shotgun (WGS) entry which is preliminary data.

Catalytic activity

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site558[4Fe-4S] cluster (UniProtKB | ChEBI); ligand shared between dimeric partners
Binding site567[4Fe-4S] cluster (UniProtKB | ChEBI); ligand shared between dimeric partners
Binding site653Mg (UniProtKB | ChEBI) of chlorophyll a B1 (UniProtKB | ChEBI); axial binding residue
Binding site661Mg (UniProtKB | ChEBI) of chlorophyll a B3 (UniProtKB | ChEBI); axial binding residue
Binding site669chlorophyll a B3 (UniProtKB | ChEBI)
Binding site670phylloquinone B (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentphotosystem I
Cellular Componentplasma membrane-derived thylakoid membrane
Molecular Function4 iron, 4 sulfur cluster binding
Molecular Functionchlorophyll binding
Molecular Functionelectron transfer activity
Molecular Functionmagnesium ion binding
Molecular Functionoxidoreductase activity
Biological Processphotosynthesis

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Photosystem I P700 chlorophyll a apoprotein A2
  • EC number
  • Alternative names
    • PsaB

Gene names

    • Name
      psaB
    • ORF names
      H6F75_03040

Organism names

  • Taxonomic identifier
  • Strain
    • FACHB-131
  • Taxonomic lineage
    Bacteria > Cyanobacteriota > Cyanophyceae > Nodosilineales > Nodosilineaceae > Nodosilinea

Accessions

  • Primary accession
    A0A8J6R5D0

Proteomes

Subcellular Location

Cellular thylakoid membrane
; Multi-pass membrane protein
Endomembrane system
; Multi-pass membrane protein

Features

Showing features for transmembrane.

TypeIDPosition(s)Description
Transmembrane51-70Helical
Transmembrane135-157Helical
Transmembrane178-199Helical
Transmembrane273-291Helical
Transmembrane334-355Helical
Transmembrane375-396Helical
Transmembrane417-438Helical
Transmembrane516-538Helical
Transmembrane575-595Helical
Transmembrane644-664Helical
Transmembrane706-726Helical

Keywords

Interaction

Subunit

The PsaA/B heterodimer binds the P700 chlorophyll special pair and subsequent electron acceptors. PSI consists of a core antenna complex that captures photons, and an electron transfer chain that converts photonic excitation into a charge separation. The cyanobacterial PSI reaction center is composed of one copy each of PsaA,B,C,D,E,F,I,J,K,L,M and X, and forms trimeric complexes.

Family & Domains

Sequence similarities

Belongs to the PsaA/PsaB family.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    733
  • Mass (Da)
    82,406
  • Last updated
    2022-05-25 v1
  • Checksum
    73069C68E62D3215
MATKFPKFSQDLAQDPTTRRLWYGIATAHDFESHDGMTEENLYQKIFASHFGHLAIIFLWTSGNLFHVAWQGNFEQWIKDPLNIKPIAHAIWDPHFGQPAVDAFSQAGSSTPVNIAFSGVYHWWYTIGMRTNTDLYTGAVFLLILSAVFLFAGWLHLQPKFRPSLSWFKNAESRLNHHLAGLFGVSSLAWTGHLVHVAIPESRGVHVGWENFLSMKPHPEGLMPFFTGNWGVYAQNPDTSSHIFGTATGSGSAILTFLGGFHPQTESLWLTDMAHHHLAIAVIFIIAGHMYRTNFGIGHSIKEILNAHKPPSGALGEGHKGLYDTYNNSLHFQLAFHLASLGVITSLVAQHMYALPPYAFMAQEYTTQAALYTHHQYIAGFIMVGAFAHGAIFLVRDYDPKANQNNVLYRVLEHKEAIISHLSWVSLFLGFHTLGLYVHNDVVVAFGTPEKQILVEPVFAQWVQACSGKLLYGFDTLLSNPDSVTQTANAVYLPGWFDAINSNKNSLFLTIGPGDFLVHHAIALGLHTTTLILVKGALDARGSKLMPDKKDFGYSFPCDGPGRGGTCDISAWDSFYLAMFWMLNTLGWVTFYWHWKHLSIWSGNVAQFNESSNYLMGWLRDYLWLNSSQLINGYNPYGMNNLAVWAWMFLFGHLVWATGFMFLISWRGYWQELIETLVWAHERTPLANLVRWKDKPVAMSIIQGRVVGLAHFTVGYILTYAAFLIASTSSRFG

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
JACJOF010000006
EMBL· GenBank· DDBJ
MBD1872448.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

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