Cytokinin dehydrogenase
In enzymology, a cytokinin dehydrogenase (EC 1.5.99.12) is an enzyme that catalyzes the chemical reaction
- N6-dimethylallyladenine + electron acceptor + H2O adenine + 3-methylbut-2-enal + reduced acceptor
| cytokinin dehydrogenase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC number | 1.5.99.12 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
The 3 substrates of this enzyme are cytokinin (here represented by N6-dimethylallyladenine), electron acceptor, and H2O, whereas its 3 products are adenine, 3-methylbut-2-enal (or other aldehyde in case of different substrate), and reduced acceptor.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with other acceptors. The systematic name of this enzyme class is N6-dimethylallyladenine:acceptor oxidoreductase. Other names in common use include N6-dimethylallyladenine:(acceptor) oxidoreductase, 6-N-dimethylallyladenine:acceptor oxidoreductase, and cytokinin oxidase/dehydrogenase abbreviated as CKX.
Structural studies
As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes 1W1O, 1W1Q, 1W1R, 1W1S, 2EXR, and 2Q4W.
As of March 2016, there have been 18 structures deposited to PDB. 16 of these were of enzymes from maize and two from Arabidopsis.
References
- Galuszka P, Frébort I, Šebela M, Sauer P, Jacobsen S, Peč P (2001). "Cytokinin oxidase or dehydrogenase? Mechanism of cytokinin degradation in cereals". Eur. J. Biochem. 268 (2): 450–461. doi:10.1046/j.1432-1033.2001.01910.x. PMID 11168382.