Q8CM25 · PSBD_THEVB
- ProteinPhotosystem II D2 protein
- GenepsbD1; psbD2
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids352 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
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. D2 is needed for assembly of a stable PSII complex.
Miscellaneous
2 of the reaction center chlorophylls (ChlD1 and ChlD2) are entirely coordinated by water.
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
Cofactor
Note: The D1/D2 heterodimer binds P680, chlorophylls that are the primary electron donor of PSII, and subsequent electron acceptors. It shares a non-heme iron and each subunit binds pheophytin, quinone, additional chlorophylls, carotenoids and lipids. There is also a Cl-1 ion associated with D1 and D2, which is required for oxygen evolution (PubMed:19219048, PubMed:21367867).
PSII binds additional chlorophylls, carotenoids and specific lipids.
PSII binds additional chlorophylls, carotenoids and specific lipids.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 117 | Mg (UniProtKB | ChEBI) of chlorophyll a ChlzD2 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 129 | pheophytin a D2 (UniProtKB | ChEBI) | ||||
Sequence: Q | ||||||
Binding site | 142 | pheophytin a D2 (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 197 | Mg (UniProtKB | ChEBI) of chlorophyll a PD2 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 214 | a plastoquinone Q(A) (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Binding site | 214 | Fe cation (UniProtKB | ChEBI); ligand shared with heterodimeric partner | ||||
Sequence: H | ||||||
Binding site | 261 | a plastoquinone Q(A) (UniProtKB | ChEBI) | ||||
Sequence: F | ||||||
Binding site | 268 | Fe cation (UniProtKB | ChEBI); ligand shared with heterodimeric partner | ||||
Sequence: H |
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 | oxygen evolving activity | |
Biological Process | photosynthetic electron transport in photosystem II |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended namePhotosystem II D2 protein
- EC number
- Short namesPSII D2 protein
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Cyanobacteriota > Cyanophyceae > Acaryochloridales > Thermosynechococcaceae > Thermosynechococcus
Accessions
- Primary accessionQ8CM25
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Cellular thylakoid membrane ; Multi-pass membrane protein
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Topological domain | 1-31 | Cytoplasmic | ||||
Sequence: MTIAIGRAPAERGWFDILDDWLKRDRFVFVG | ||||||
Transmembrane | 32-53 | Helical | ||||
Sequence: WSGILLFPCAYLALGGWLTGTT | ||||||
Topological domain | 54-108 | Lumenal | ||||
Sequence: FVTSWYTHGLASSYLEGCNFLTVAVSTPANSMGHSLLLLWGPEAQGDFTRWCQLG | ||||||
Transmembrane | 109-131 | Helical | ||||
Sequence: GLWTFIALHGAFGLIGFMLRQFE | ||||||
Topological domain | 132-140 | Cytoplasmic | ||||
Sequence: IARLVGVRP | ||||||
Transmembrane | 141-160 | Helical | ||||
Sequence: YNAIAFSAPIAVFVSVFLIY | ||||||
Topological domain | 161-193 | Lumenal | ||||
Sequence: PLGQSSWFFAPSFGVAAIFRFLLFFQGFHNWTL | ||||||
Transmembrane | 194-217 | Helical | ||||
Sequence: NPFHMMGVAGVLGGALLCAIHGAT | ||||||
Topological domain | 218-265 | Cytoplasmic | ||||
Sequence: VENTLFQDGEGASTFRAFNPTQAEETYSMVTANRFWSQIFGIAFSNKR | ||||||
Transmembrane | 266-288 | Helical | ||||
Sequence: WLHFFMLFVPVTGLWMSAIGVVG | ||||||
Topological domain | 289-352 | Lumenal | ||||
Sequence: LALNLRSYDFISQEIRAAEDPEFETFYTKNLLLNEGIRAWMAPQDQPHENFVFPEEVLPRGNAL |
Keywords
- Cellular component
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000359603 | 1-352 | Photosystem II D2 protein | |||
Sequence: MTIAIGRAPAERGWFDILDDWLKRDRFVFVGWSGILLFPCAYLALGGWLTGTTFVTSWYTHGLASSYLEGCNFLTVAVSTPANSMGHSLLLLWGPEAQGDFTRWCQLGGLWTFIALHGAFGLIGFMLRQFEIARLVGVRPYNAIAFSAPIAVFVSVFLIYPLGQSSWFFAPSFGVAAIFRFLLFFQGFHNWTLNPFHMMGVAGVLGGALLCAIHGATVENTLFQDGEGASTFRAFNPTQAEETYSMVTANRFWSQIFGIAFSNKRWLHFFMLFVPVTGLWMSAIGVVGLALNLRSYDFISQEIRAAEDPEFETFYTKNLLLNEGIRAWMAPQDQPHENFVFPEEVLPRGNAL |
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. Part of a photosystem II (PSII) assembly intermediate complex PSII-I; crystallized from a strain deleted of psbJ, it forms monomeric PSII before addition of the oxygen evolving complex. PSII-I includes 3 assembly factors not found in mature PSII (Psb27, Psb28 and Psb34) (PubMed:33846594).
Protein-protein interaction databases
Structure
Sequence
- Sequence statusComplete
- Length352
- Mass (Da)39,361
- Last updated2003-03-01 v1
- ChecksumC5D91543CD148FD4
Mass Spectrometry
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
BA000039 EMBL· GenBank· DDBJ | BAC08007.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
BA000039 EMBL· GenBank· DDBJ | BAC09182.1 EMBL· GenBank· DDBJ | Genomic DNA |