| EC |
1.5.99.12 |
| Accepted name: |
cytokinin dehydrogenase |
| Reaction: |
N6-dimethylallyladenine + acceptor + H2O = adenine + 3-methylbut-2-enal + reduced acceptor |
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For diagram of reaction, click here |
| Glossary: |
zeatin = (E)-2-methyl-4-(9H-purin-6-ylamino)but-2-en-1-ol = (E)-N6-(4-hydroxy-3-methylbut-2-enyl)adenine |
| Other name(s): |
N6-dimethylallyladenine:(acceptor) oxidoreductase; 6-N-dimethylallyladenine:acceptor oxidoreductase; OsCKX2; CKX; cytokinin oxidase/dehydrogenase |
| Systematic name: |
N6-dimethylallyladenine:acceptor oxidoreductase |
| Comments: |
A flavoprotein(FAD). Catalyses the oxidation of cytokinins, a family of N6-substituted adenine derivatives that are plant hormones, where the substituent is a dimethylallyl or other prenyl group. Although this activity was previously thought to be catalysed by a hydrogen-peroxide-forming oxidase, this enzyme does not require oxygen for activity and does not form hydrogen peroxide. 2,6-Dichloroindophenol, methylene blue, nitroblue tetrazolium, phenazine methosulfate and Cu(II) in the presence of imidazole can act as acceptors. This enzyme plays a part in regulating rice-grain production, with lower levels of the enzyme resulting in enhanced grain production [2]. |
| Links to other databases: |
BRENDA, EXPASY, KEGG, METACYC, PDB, CAS registry number: 55326-39-1 |
| References: |
| 1. |
Galuszka, P., Frebort, I., Sebela, M., Jacobsen, S. and Pec, P. Cytokinin oxidase or dehydrogenase? Mechanism of cytokinin degradation in plants. Eur. J. Biochem. 268 (2001) 450–461. [PMID: 11168382] |
| 2. |
Ashikari, M., Sakakibara, H., Lin, S., Yamamoto, T., Takashi, T., Nishimura, A., Angeles, E.R., Qian, Q., Kitano, H. and Matsuoka, M. Cytokinin oxidase regulates rice grain production. Science 309 (2005) 741–745. [PMID: 15976269] |
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| [EC 1.5.99.12 created 2001] |
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