Cytokinin dehydrogenase

Cytokinin dehydrogenase
Identifiers
EC no.1.5.99.12
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
Search
PMCarticles
PubMedarticles
NCBIproteins

Cytokinin dehydrogenase (EC 1.5.99.12) is an enzyme that catalyzes the chemical reaction

N6-isopentenyladenine
 
H2O
 
H2O
 
 
+ reduced
acceptor
 
+
 
3-methyl-2-butenal

The three substrates of this enzyme are a cytokinin such as N6-isopentenyladenine, an electron acceptor, and water. Its products are adenine, 3-methyl-2-butenal (or other aldehyde in case of different substrates), and the corresponding reduced acceptor.[1][2][3]

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 2026, there have been 18 structures recorded.[4]

References

  1. ^ Enzyme 1.5.99.12 at KEGG Pathway Database.
  2. ^ Galuszka, Petr; Frébort, Ivo; Šebela, Marek; Sauer, Pavel; Jacobsen, Susanne; Peč, Pavel (2001). "Cytokinin oxidase or dehydrogenase?". European Journal of Biochemistry. 268 (2): 450–461. doi:10.1046/j.1432-1033.2001.01910.x. PMID 11168382.
  3. ^ Ashikari, Motoyuki; Sakakibara, Hitoshi; Lin, Shaoyang; Yamamoto, Toshio; Takashi, Tomonori; Nishimura, Asuka; Angeles, Enrique R.; Qian, Qian; Kitano, Hidemi; Matsuoka, Makoto (2005). "Cytokinin Oxidase Regulates Rice Grain Production". Science. 309 (5735): 741–745. doi:10.1126/science.1113373. PMID 15976269.
  4. ^ "Cytokinin dehydrogenase". ebi.ac.uk. Protein Data Bank in Europe. Retrieved 2026-02-20.