A0A218LRQ5 · A0A218LRQ5_9POAL
- ProteinPhotosystem I P700 chlorophyll a apoprotein A2
- GenepsaB
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids734 (go to sequence)
- Protein existenceInferred from homology
- Annotation score3/5
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-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.
Catalytic activity
- hnu + oxidized [2Fe-2S]-[ferredoxin] + reduced [plastocyanin] = oxidized [plastocyanin] + reduced [2Fe-2S]-[ferredoxin]
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 559 | [4Fe-4S] cluster (UniProtKB | ChEBI); ligand shared between dimeric partners | ||||
Sequence: C | ||||||
Binding site | 568 | [4Fe-4S] cluster (UniProtKB | ChEBI); ligand shared between dimeric partners | ||||
Sequence: C | ||||||
Binding site | 654 | Mg (UniProtKB | ChEBI) of chlorophyll a B1 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 662 | Mg (UniProtKB | ChEBI) of chlorophyll a B3 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: M | ||||||
Binding site | 670 | chlorophyll a B3 (UniProtKB | ChEBI) | ||||
Sequence: Y | ||||||
Binding site | 671 | phylloquinone B (UniProtKB | ChEBI) | ||||
Sequence: W |
GO annotations
all annotations | all molecular function | nucleotide binding | molecular_function | nucleic acid binding | dna binding | chromatin binding | dna-binding transcription factor activity | rna binding | cytoskeletal motor activity | catalytic activity | nuclease activity | signaling receptor binding | structural molecule activity | transporter activity | binding | protein binding | translation factor activity, rna binding | lipid binding | kinase activity | transferase activity | hydrolase activity | oxygen binding | enzyme regulator activity | carbohydrate binding | signaling receptor activity | translation regulator activity | transcription regulator activity | other molecular function | all biological process | carbohydrate metabolic process | generation of precursor metabolites and energy | nucleobase-containing compound metabolic process | dna metabolic process | translation | lipid metabolic process | transport | response to stress | cell cycle | cell communication | signal transduction | cell-cell signaling | multicellular organism development | circadian rhythm | biological_process | metabolic process | catabolic process | biosynthetic process | response to light stimulus | response to external stimulus | tropism | response to biotic stimulus | response to abiotic stimulus | response to endogenous stimulus | embryo development | post-embryonic development | fruit ripening | abscission | pollination | flower development | cellular process | programmed cell death | photosynthesis | cellular component organization | cell growth | protein metabolic process | cellular homeostasis | secondary metabolic process | reproductive process | cell differentiation | protein modification process | growth | epigenetic regulation of gene expression | response to chemical | anatomical structure development | regulation of molecular function | other biological process | all cellular component | cellular_component | extracellular region | cell wall | intracellular anatomical structure | nucleus | nuclear envelope | nucleoplasm | nucleolus | cytoplasm | mitochondrion | lysosome | endosome | vacuole | peroxisome | endoplasmic reticulum | golgi apparatus | cytosol | ribosome | cytoskeleton | plasma membrane | chloroplast | plastid | thylakoid | membrane | external encapsulating structure | other cellular component | |||
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Aspect | Term | |
---|---|---|
Cellular Component | chloroplast thylakoid membrane | |
Cellular Component | photosystem I | |
Molecular Function | 4 iron, 4 sulfur cluster binding | |
Molecular Function | chlorophyll binding | |
Molecular Function | electron transfer activity | |
Molecular Function | magnesium ion binding | |
Molecular Function | oxidoreductase activity | |
Biological Process | photosynthesis |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended namePhotosystem I P700 chlorophyll a apoprotein A2
- EC number
- Alternative names
Gene names
Encoded on
- Chloroplast
Organism names
- Organism
- Taxonomic lineageEukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > Liliopsida > Poales > Poaceae > BOP clade > Pooideae > Triticodae > Triticeae > Hordeinae > Elymus
Accessions
- Primary accessionA0A218LRQ5
Subcellular Location
UniProt Annotation
GO Annotation
Membrane ; Multi-pass membrane protein
Plastid, chloroplast thylakoid membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 135-157 | Helical | ||||
Sequence: LYTGALFLLFLSTLSLIAGWLHL | ||||||
Transmembrane | 178-199 | Helical | ||||
Sequence: HLSGLFGVSSLAWTGHLVHVAI | ||||||
Transmembrane | 330-349 | Helical | ||||
Sequence: IHFQLGLALASLGVITSLVA | ||||||
Transmembrane | 377-396 | Helical | ||||
Sequence: YIAGFIMTGAFAHGAIFFIR | ||||||
Transmembrane | 417-438 | Helical | ||||
Sequence: AIISHLSWASLFLGFHTLGLYV | ||||||
Transmembrane | 517-539 | Helical | ||||
Sequence: FLVHHAIALGLHTTTLILVKGAL | ||||||
Transmembrane | 575-596 | Helical | ||||
Sequence: AFYLAVFWMLNTIGWVTFYWHW | ||||||
Transmembrane | 645-665 | Helical | ||||
Sequence: VWAWMFLFGHLVWATGFMFLI | ||||||
Transmembrane | 707-727 | Helical | ||||
Sequence: LVGLAHFSVGYIFTYAAFLIA |
Keywords
- Cellular component
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 eukaryotic PSI reaction center is composed of at least 11 subunits.
Structure
Sequence
- Sequence statusComplete
- Length734
- Mass (Da)82,585
- Last updated2017-09-27 v1
- ChecksumF1E8D6EFC4C94122