A0A2S6CPX1 · A0A2S6CPX1_9CYAN

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 site575[4Fe-4S] cluster (UniProtKB | ChEBI); ligand shared between dimeric partners
Binding site584[4Fe-4S] cluster (UniProtKB | ChEBI); ligand shared between dimeric partners
Binding site676Mg (UniProtKB | ChEBI) of chlorophyll a' A1 (UniProtKB | ChEBI); axial binding residue
Binding site684Mg (UniProtKB | ChEBI) of chlorophyll a A3 (UniProtKB | ChEBI); axial binding residue
Binding site692chlorophyll a A3 (UniProtKB | ChEBI)
Binding site693phylloquinone A (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 A1
  • EC number
  • Alternative names
    • PsaA

Gene names

    • Name
      psaA
    • ORF names
      CUN59_19010

Organism names

Accessions

  • Primary accession
    A0A2S6CPX1

Proteomes

Subcellular Location

Cellular thylakoid membrane
; Multi-pass membrane protein
Membrane
; Multi-pass membrane protein

Features

Showing features for transmembrane.

TypeIDPosition(s)Description
Transmembrane73-93Helical
Transmembrane157-181Helical
Transmembrane294-312Helical
Transmembrane353-373Helical
Transmembrane393-415Helical
Transmembrane436-457Helical
Transmembrane538-557Helical
Transmembrane592-612Helical
Transmembrane665-687Helical

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

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    751
  • Mass (Da)
    83,008
  • Last updated
    2018-07-18 v1
  • Checksum
    5C704265DB9323A9
MTISPPEREEKKARVIVDNDPVPTSFEKWAKPGHFDRSLSRGPKTTTWIWNLHALAHDFDTHTSDLEDISRKIFAAHFGHLAVVAIWLSGMLFHGAKFSNYEAWLADPLGVKPSAQTVWSIVGQDILNGDMGGGFRGIQITSGLFQVWRGWGITSSFQLYVTAIGGLVLAGLFLFAGWFHYHKRAPKLEWFQNVESMLNHHLSVLLGCGSLGWAGHLIHVSAPINKLLDAGVAAKDIPLPHELLFDTAKMAELYPGFASGLTPFFTLNWGAYADILTFKGGLNPVTGGLWMTDISHHHLAIAVLFIIAGHMYRTNWGIGHSIKDILEAHKGPFTGEGHKGLYENMTTSWHAQLATNLAFLGSLTIIIAHHMYAMPPYPYLATDYATQLCIFTHHIWIGGFLIVGGAAHAAIFMVRDYDPVVNQNNVLDRVIRHRDAIISHLNWVCIFLGFHSFGLYIHNDTMRALGRPQDMFSDAAIKLQPVFAQWVQSLHSLAPGNTAPNALEVVSHAFGGGIVAVGGKVAMMPIALGTADFMVHHIHAFTIHVTVLILLKGVLYARSSRLIPDKANLGFRFPCDGPGRGGTCQVSGWDHIFLGLFWMYNSLSIVIFHFSWKMQSDVWGTIEDGTVNHITAGNFAESAITINGWLRDFLWAQATQVINSYGSELSAYGLMFLGAHFVWAFSLMFLFSGRGYWQELIESIVWAHNKLKVAPTIQPRALSITQGRAVGVAHYLLGGIATTWAFFHAHILSVG

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
PGEM01000171
EMBL· GenBank· DDBJ
PPJ61788.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

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