| tetrahydroberberine oxidase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.3.3.8 | ||||||||
| CAS no. | 114705-00-9 | ||||||||
| 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 | ||||||||
| |||||||||
(S)-Tetrahydroberberine oxidase (EC 1.3.3.8) is an enzyme that catalyzes the final transformation in the biosynthesis of berberine, a quaternary benzylisoquinoline alkaloid of the protoberberine structural subgroup. [1] [2] This reaction pathway catalyzes the four-electron oxidation of (S)-tetrahydroberberine (also known as (S)-canadine) in the presence of oxygen to produce berberine and hydrogen peroxide. [3]
This enzyme belongs to the family known as oxidoreductases, in this instance the CH-CH moiety acts as the electron donor with oxygen acting as the electron acceptor. The systematic name of this enzyme is (S)-tetrahydroberberine:oxygen oxidoreductase; but it is also known as (S)-THB oxidase, tetrahydroberberine oxidase, and decreasingly, as (S)-tetrahydroprotoberberine oxidase. [4] [5]
Other quaternary benzylisoquinoline alkaloids can be produced by this enzyme, provided that their precursor has (S} configuration at the centre next to the nitrogen. For example, (S)-isocorypalmine is oxidised to columbamine; tetrahydropalmatine to palmatine, and tetrahydropapaverine to papaverine. [3] [6]
