Tetrahydroberberine oxidase

In enzymology, a tetrahydroberberine oxidase (EC 1.3.3.8) is an enzyme that catalyzes the chemical reaction

(S)-tetrahydroberberine + 2 O₂ berberine + 2 H₂O₂

Thus, the two substrates of this enzyme are (S)-tetrahydroberberine and O₂, whereas its two products are berberine and H₂O₂.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with oxygen as acceptor. The systematic name of this enzyme class is (S)-tetrahydroberberine:oxygen oxidoreductase. This enzyme is also called (S)-THB oxidase. This enzyme participates in alkaloid biosynthesis.

References

• Amann M, Nagakura N and Zenk MH (1984). "(S)-Tetrahydroprotoberberine oxidase the final enzyme in protoberberine biosynthesis". Tetrahedron Lett. 25 (9): 953–954. doi:10.1016/S0040-4039(01)80071-X. 
• Okada N, Shinmyo A, Okada H and Yamada Y (1988). "Purification and characterization of (S)-tetrahydroberberine oxidase from cultured Coptis japonica cells". Phytochemistry 27 (4): 979–982. doi:10.1016/0031-9422(88)80255-3.