| Methylamine dehydrogenase (amicyanin) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.4.9.1 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| |||||||||
Methylamine dehydrogenase (amicyanin) (EC 1.4.9.1, MADH, amine dehydrogenase, primary-amine dehydrogenase, methylamine:amicyanin oxidoreductase (deaminating)) catalyzes the reduction of copper-dependent electron-carrier amicyanin via oxidation of methylamine to formaldehyde. [1] [2] [3] [4] [5]
This reaction requires the post-translational formation of a tryptophan tryptophylquinone (TTQ) cofactor. [6] MADH forms a tetramer of two light-chain and two heavy-chain protomers. The TTQ cofactor is located in the light-chain and is formed from oxidative coupling between Trp57 and Trp108 ( Paracoccus denitrificans numbering) catalyzed by the diheme enzyme MauG. [6]
In P. denitrificans, methylamine dehydrogenase transiently forms a ternary complex to catalyze methylamine-dependent cytochrome c-551i reduction. [7] Within this complex, electrons are transferred from the TTQ cofactor of MADH to the Type 1 copper center of amicyanin, and then to the heme of the cytochrome.
