IUBMB Enzyme Nomenclature


Accepted name: reticuline oxidase

Reaction: (S)-reticuline + O2 = (S)-scoulerine + H2O2

For diagram click here.

Other name(s): BBE; berberine bridge enzyme; berberine-bridge-forming enzyme; tetrahydroprotoberberine synthase

Systematic name: (S)-reticuline:oxygen oxidoreductase (methylene-bridge-forming)

Comments: Contains FAD. The enzyme from the plant Eschscholtzia californica binds the cofactor covalently [3]. Acts on (S)-reticuline and related compounds, converting the N-methyl group into the methylene bridge ('berberine bridge') of (S)-tetrahydroprotoberberines. The product of the reaction, (S)-scoulerine, is a precursor of protopine, protoberberine and benzophenanthridine alkaloid biosynthesis in plants.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 152232-28-5


1. Steffens, P., Nagakura, N. and Zenk, M.H. The berberine bridge forming enzyme in tetrahydroprotoberberine biosynthesis. Tetrahedron Lett. 25 (1984) 951-952.

2. Dittrich, H. and Kutchan, T.M. Molecular cloning, expression and induction of the berberine bridge enzyme, an enzyme essential to the formation of benzophenanthridine alkaloids in the response of plants to pathogenic attack. Proc. Natl. Acad. Sci. USA 88 (1991) 9969-9973. [PMID: 1946465]

3. Kutchan, T.M. and Dittrich, H. Characterization and mechanism of the berberine bridge enzyme, a covalently flavinylated oxidase of benzophenanthridine alkaloid biosynthesis in higher plants. J. Biol. Chem. 270 (1995) 24475-24481. [PMID: 7592663]

[EC created 1989 as EC, transferred 2002 to EC]

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