A0A9X5E388 · A0A9X5E388_9CYAN
- ProteinPhotosystem II protein D1
- GenepsbA
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids353 (go to sequence)
- Protein existenceInferred from homology
- Annotation score4/5
Function
function
Photosystem II (PSII) is a light-driven water:plastoquinone oxidoreductase that uses light energy to abstract electrons from H2O, generating O2 and a proton gradient subsequently used for ATP formation. It consists of a core antenna complex that captures photons, and an electron transfer chain that converts photonic excitation into a charge separation. The D1/D2 (PsbA/PsbD) reaction center heterodimer binds P680, the primary electron donor of PSII as well as several subsequent electron acceptors.
Miscellaneous
2 of the reaction center chlorophylls (ChlD1 and ChlD2) are entirely coordinated by water.
Cyanobacteriota usually contain more than 2 copies of the psbA gene.
Herbicides such as atrazine, BNT, diuron or ioxynil bind in the Q(B) binding site and block subsequent electron transfer.
Catalytic activity
- 2 a plastoquinone + 2 H2O + 4 hnu = 2 a plastoquinol + O2
2 a plastoquinone RHEA-COMP:9562 + 2 CHEBI:15377 + 4 CHEBI:30212 = 2 a plastoquinol RHEA-COMP:9561 + CHEBI:15379
Features
Showing features for binding site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 118 | Mg (UniProtKB | ChEBI) of chlorophyll a ChlzD1 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 126 | pheophytin a D1 (UniProtKB | ChEBI) | ||||
Sequence: Y | ||||||
Site | 161 | Tyrosine radical intermediate | ||||
Sequence: Y | ||||||
Binding site | 170 | [CaMn4O5] cluster (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 189 | [CaMn4O5] cluster (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Site | 190 | Stabilizes free radical intermediate | ||||
Sequence: H | ||||||
Binding site | 198 | Mg (UniProtKB | ChEBI) of chlorophyll a PD1 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 215 | Fe cation (UniProtKB | ChEBI); ligand shared with heterodimeric partner | ||||
Sequence: H | ||||||
Binding site | 215 | a quinone B (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Binding site | 264-265 | a quinone B (UniProtKB | ChEBI) | ||||
Sequence: SF | ||||||
Binding site | 272 | Fe cation (UniProtKB | ChEBI); ligand shared with heterodimeric partner | ||||
Sequence: H | ||||||
Binding site | 332 | [CaMn4O5] cluster (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Binding site | 333 | [CaMn4O5] cluster (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 342 | [CaMn4O5] cluster (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 344 | [CaMn4O5] cluster (UniProtKB | ChEBI) | ||||
Sequence: A | ||||||
Site | 344-345 | Cleavage; by CtpA | ||||
Sequence: AA |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | photosystem II | |
Cellular Component | plasma membrane-derived thylakoid membrane | |
Molecular Function | chlorophyll binding | |
Molecular Function | electron transporter, transferring electrons within the cyclic electron transport pathway of photosynthesis activity | |
Molecular Function | iron ion binding | |
Molecular Function | oxidoreductase activity, acting on diphenols and related substances as donors, oxygen as acceptor | |
Biological Process | photosynthetic electron transport in photosystem II | |
Biological Process | response to herbicide |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended namePhotosystem II protein D1
- EC number
- Short namesPSII D1 protein
- Alternative names
Gene names
Organism names
- Organism
- Strain
- Taxonomic lineageBacteria > Cyanobacteriota > Cyanophyceae > Nostocales > Scytonemataceae > Scytonema
Accessions
- Primary accessionA0A9X5E388
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Cellular thylakoid membrane ; Multi-pass membrane protein
Membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 29-55 | Helical | ||||
Sequence: YIGWFGVLMIPTLLAATTCFIVAFIAA | ||||||
Transmembrane | 109-127 | Helical | ||||
Sequence: GGPYQLVIFHFLIGVFCYM | ||||||
Transmembrane | 139-160 | Helical | ||||
Sequence: MRPWICVAYSAPVAAATAVFLI | ||||||
Transmembrane | 200-218 | Helical | ||||
Sequence: LGVAGVFGGALFSAMHGSL | ||||||
Transmembrane | 270-295 | Helical | ||||
Sequence: ALHFFLAAWPVIGIWFTSLGISTMAF |
Keywords
- Cellular component
PTM/Processing
Features
Showing features for chain, propeptide.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_5041023909 | 1-344 | Photosystem II protein D1 | |||
Sequence: MTTTLQRRESASLWEQFCNWVASTENRLYIGWFGVLMIPTLLAATTCFIVAFIAAPPVDIDGIREPVAGSLIYGNNIISGAVVPSSNAIGLHFYPIWEAASLDEWLYNGGPYQLVIFHFLIGVFCYMGREWELSYRLGMRPWICVAYSAPVAAATAVFLIYPIGQGSFSDGMPLGISGTFNFMLVFQAEHNILMHPFHQLGVAGVFGGALFSAMHGSLVTSSLVRETTETESQNYGYKFGQEEETYNIVAAHGYFGRLIFQYASFNNSRALHFFLAAWPVIGIWFTSLGISTMAFNLNGFNFNQSVVDSQGHAIGTWADILNRANLGMEVMHERNAHNFPLDLA | ||||||
Propeptide | PRO_5041023908 | 345-353 | ||||
Sequence: AVEAPSLNG |
Post-translational modification
C-terminally processed by CtpA; processing is essential to allow assembly of the oxygen-evolving complex and thus photosynthetic growth.
Tyr-161 forms a radical intermediate that is referred to as redox-active TyrZ, YZ or Y-Z.
Interaction
Subunit
PSII is composed of 1 copy each of membrane proteins PsbA, PsbB, PsbC, PsbD, PsbE, PsbF, PsbH, PsbI, PsbJ, PsbK, PsbL, PsbM, PsbT, PsbX, PsbY, PsbZ, Psb30/Ycf12, peripheral proteins PsbO, CyanoQ (PsbQ), PsbU, PsbV and a large number of cofactors. It forms dimeric complexes.
Structure
Sequence
- Sequence statusComplete
- Length353
- Mass (Da)38,965
- Last updated2023-11-08 v1
- ChecksumFBAE51EBB50A1C1D