PROSITE documentation PDOC00674
Oxygen oxidoreductases covalent FAD-binding site


Some oxygen-dependent oxidoreductases are flavoproteins that contains a covalently bound FAD group which is attached to a histidine via an 8-α-(N3-histidyl)-riboflavin linkage. These proteins are:

  • (R)-6-hydroxynicotine oxidase (EC (6-HDNO) [1], a bacterial enzyme that catalyzes the oxygen-dependent degradation of 6-hydroxynicotine into 6-hydroxypyrid-N-methylosmine.
  • Plant reticuline oxidase (EC [2] (berberine-bridge-forming enzyme), an enzyme that catalyzes the oxidation of (S)-reticuline into (S)- scoulerine in the pathway leading to benzophenanthridine alkaloids.
  • L-gulonolactone oxidase (EC (l-gulono-γ-lactone oxidase) [3], a mammalian enzyme which catalyzes the oxidation of L-gulono-1,4-lactone to L-xylo-hexulonolactone which spontaneously isomerizes to L-ascorbate.
  • D-arabinono-1,4-lactone oxidase (EC (L-galactonolactone oxidase), a yeast enzyme involved in the biosynthesis of D-erythroascorbic acid [4].
  • Mitomycin radical oxidase [5], a bacterial protein involved in mitomycin resistance and that probably oxidizes the reduced form of mitomycins.
  • Cytokinin oxidase (EC, a plant enzyme.
  • Rhodococcus fascians fasciation locus protein fas5.

The region around the histidine that binds the FAD group is conserved in these enzymes and can be used as a signature pattern.

Last update:

April 2006 / Pattern revised.


Technical section

PROSITE method (with tools and information) covered by this documentation:

OX2_COVAL_FAD, PS00862; Oxygen oxidoreductases covalent FAD-binding site  (PATTERN)


1AuthorsBrandsch R. Hinkkanen A.E. Mauch L. Nagursky H. Decker K.
Title6-Hydroxy-D-nicotine oxidase of Arthrobacter oxidans. Gene structure of the flavoenzyme and its relationship to 6-hydroxy-L-nicotine oxidase.
SourceEur. J. Biochem. 167:315-320(1987).
PubMed ID3622516

2AuthorsDittrich H. Kutchan T.M.
TitleMolecular cloning, expression, and induction of berberine bridge enzyme, an enzyme essential to the formation of benzophenanthridine alkaloids in the response of plants to pathogenic attack.
SourceProc. Natl. Acad. Sci. U.S.A. 88:9969-9973(1991).
PubMed ID1946465

3AuthorsKoshizaka T. Nishikimi M. Ozawa T. Yagi K.
TitleIsolation and sequence analysis of a complementary DNA encoding rat liver L-gulono-gamma-lactone oxidase, a key enzyme for L-ascorbic acid biosynthesis.
SourceJ. Biol. Chem. 263:1619-1621(1988).
PubMed ID3338984

4AuthorsHuh W.-K. Lee B.-H. Kim S.-T. Kim Y.-R. Rhie G.-E. Baek Y.-W. Hwang C.-S. Lee J.-S. Kang S.-O.
TitleD-erythroascorbic acid is an important antioxidant molecule in Saccharomyces cerevisiae.
SourceMol. Microbiol. 30:895-903(1998).
PubMed ID10094636

5AuthorsAugust P.R. Flickinger M.C. Sherman D.H.
TitleCloning and analysis of a locus (mcr) involved in mitomycin C resistance in Streptomyces lavendulae.
SourceJ. Bacteriol. 176:4448-4454(1994).
PubMed ID7517396

PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see prosite_license.html.


View entry in original PROSITE document format
View entry in raw text format (no links)