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Updated: Aug 30, 2026

Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
The C-4 stereochemistry of leucocyanidin substrates for anthocyanidin synthase affects product selectivity
Jonathan J Turnbull1, Michael J Nagle, Jürgen F Seibel
1The Oxford Centre for Molecular Sciences and The Dyson Perrins Laboratory, The Department of Chemistry, South Parks Road, Oxford OX1 3QY, UK.
Abstract:
Anthocyanidin synthase (ANS), an iron(II) and 2-oxoglutarate (2OG) dependent oxygenase, catalyses the penultimate step in anthocyanin biosynthesis by oxidation of the 2R,3S,4S-cis-leucoanthocyanidins. It has been believed that in vivo the products of ANS are the anthocyanidins. However, in vitro studies on ANS using optically active cis- and trans-leucocyanidin substrates identified cyanidin as only a minor product; instead both quercetin and dihydroquercetin are products with the distribution being dependent on the C-4 stereochemistry of the leucocyanidin substrates.
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