Thymine dioxygenase
| Thymine dioxygenase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.14.11.6 | ||||||||
| CAS no. | 37256-67-0 | ||||||||
| 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 | ||||||||
| |||||||||
Thymine dioxygenase (EC 1.14.11.6) is an enzyme that catalyzes the chemical reaction
The enzyme oxidises thymine to give 5-hydroxymethyluracil.[1][2]
The enzyme is an alpha-ketoglutarate-dependent hydroxylase with systematic name thymine,2-oxoglutarate:oxygen oxidoreductase (7-hydroxylating). Other names in common use include thymine 7-hydroxylase, 5-hydroxy-methyluracil dioxygenase, and 5-hydroxymethyluracil oxygenase.[3]
Mechanism
The enzyme is a non-heme iron protein with ferryl active site where Fe(IV)=O is the species that transfers its oxygen to the substrate.[4]
The mechanism requires 2-oxoglutaric acid to activate the iron oxygen complex, and this gives succinic acid and carbon dioxide when the second atom of the molecular oxygen is removed. Ascorbic acid is also required to increase the turnover number of the enzyme by reducing any iron converted to Fe(III) back to the required Fe(II).[5][6][7]
References
- ^ Bankel L, Holme E, Lindstedt G, Lindstedt S (1972). "Oxygenases involved in thymine and thymidine metabolism in Neurospora crassa". FEBS Lett. 21 (2): 135–138. Bibcode:1972FEBSL..21..135B. doi:10.1016/0014-5793(72)80121-2. PMID 11946494.
- ^ Liu CK, Hsu CA, Abbott MT (1973). "Catalysis of three sequential dioxygenase reactions by thymine 7-hydroxylase". Arch. Biochem. Biophys. 159 (1): 180–7. doi:10.1016/0003-9861(73)90443-8. PMID 4274083.
- ^ Enzyme 1.14.11.6 at KEGG Pathway Database.
- ^ Mbenza NM, Vadakkedath PG, McGillivray DJ, Leung IK (December 2017). "NMR studies of the non-haem Fe(II) and 2-oxoglutarate-dependent oxygenases". J. Inorg. Biochem. 177: 384–394. doi:10.1016/j.jinorgbio.2017.08.032. PMID 28893416.
- ^ Warn-Cramer BJ, Macrander LA, Abbott MT (1983). "Markedly different ascorbate dependencies of the sequential alpha-ketoglutarate dioxygenase reactions catalyzed by an essentially homogeneous thymine 7-hydroxylase from Rhodotorula glutinis". J. Biol. Chem. 258 (17): 10551–7. doi:10.1016/S0021-9258(17)44491-7. PMID 6684117.
- ^ Hibi M, Ogawa J (May 2014). "Characteristics and biotechnology applications of aliphatic amino acid hydroxylases belonging to the Fe(II)/α-ketoglutarate-dependent dioxygenase superfamily". Applied Microbiology and Biotechnology. 98 (9): 3869–3876. doi:10.1007/s00253-014-5620-z. PMID 24682483.
- ^ Clifton IJ, Hsueh LC, Baldwin JE, Harlos K, Schofield CJ (2001). "Structure of proline 3-hydroxylase. Evolution of the family of 2-oxoglutarate dependent oxygenases". Eur. J. Biochem. 268 (24): 6625–36. doi:10.1046/j.0014-2956.2001.02617.x. PMID 11737217.