Trimethyllysine dioxygenase
Class of enzymes
From Wikipedia, the free encyclopedia
Trimethyllysine dioxygenase (TMLH; EC 1.14.11.8) is an enzyme that catalyzes the chemical reaction
-3-hydroxy-N(6),N(6),N(6)-trimethyl-L-lysine(1+).svg)
| Trimethyllysine dioxygenase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.14.11.8 | ||||||||
| CAS no. | 74622-49-4 | ||||||||
| Databases | |||||||||
| BRENDA | enzyme data | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | enzyme entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| Rhea | reactions | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
TMLH is a member of the alpha-ketoglutarate-dependent hydroxylases superfamily. It oxidises trimethyl-L-lysine to the product (3S)-3-hydroxy-N6,N6,N6-trimethyl-L-lysine.[1][2]
This enzyme is an oxidase with the systematic name N6,N6,N6-trimethyl-L-lysine,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating). Other names in common use include trimethyllysine alpha-ketoglutarate dioxygenase, TML-alpha-ketoglutarate dioxygenase, TML hydroxylase, 6-N,6-N,6-N-trimethyl-L-lysine,2-oxoglutarate:oxygen oxidoreductase, and (3-hydroxylating). This enzyme participates in lysine degradation and L-carnitine biosynthesis.[1]
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.[3][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]
