EC 188.8.131.52 Enzyme
oxyS (gene name);
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With NADH or NADPH as one donor, and incorporation of one atom of oxygen into the other donor
5a,11a-dehydrotetracycline,NADPH:oxygen oxidoreductase (5-hydroxylating)
5a,11a-dehydrotetracycline + NADPH + H+ + O2 = 5a,11a-dehydrooxytetracycline + NADP+ + H2O [RN:
The enzyme, characterized from the bacterium Streptomyces rimosus, is bifunctional, catalysing two successive monooxygenation reactions. It starts by catalysing the stereospecific hydroxylation of anhydrotetracycline at C-6 (EC
). If the released product is captured by EC
, 5a,11a-dehydrotetracycline dehydrogenase (OxyR), it is reduced to tetracycline. However, if the released product is recaptured by OxyS, it performs an additional hydroxylation at C-5, producing 5a,11a-dehydrooxytetracycline, which, following the action of OxyR, becomes oxytetracycline.
EC 184.108.40.206 created 2016
Biosynthesis of type II polyketide products
Biosynthesis of secondary metabolites
anhydrotetracycline 6-monooxygenase / 5a,11a-dehydrotetracycline 5-monooxygenase
Binnie C, Warren M, Butler MJ
Cloning and heterologous expression in Streptomyces lividans of Streptomyces rimosus genes involved in oxytetracycline biosynthesis.
J Bacteriol 171:887-95 (1989)
Miller PA, Saturnelli A, Martin JH, Itscher LA, Bohonos N
A new family of tetracycline precursors. N-demethylanhydrotetracyclines.
Biochem Biophys Res Commun 16:285-91 (1964)
Vancurova I, Volc J, Flieger M, Neuzil J, Novotna J, Vlach J, Behal V
Isolation of pure anhydrotetracycline oxygenase from Streptomyces aureofaciens.
Biochem J 253:263-7 (1988)
Wang P, Bashiri G, Gao X, Sawaya MR, Tang Y
Uncovering the enzymes that catalyze the final steps in oxytetracycline biosynthesis.
J Am Chem Soc 135:7138-41 (2013)
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