CATH Classification

Domain Context

CATH Clusters

Superfamily B-lactam Antibiotic, Isopenicillin N Synthase; Chain
Functional Family Flavonol synthase

Enzyme Information

1.14.20.4
Anthocyanidin synthase.
based on mapping to UniProt Q96323
A (2R,3S,4S)-leucoanthocyanidin + 2-oxoglutarate + O(2) = an anthocyanidin + succinate + CO(2) + 2 H(2)O.
-!- Is involved in the pathway by which many flowering plants make anthocyanin flower pigments (glycosylated anthocyandins). -!- Hydroxylates the C-3 carbon, followed by a trans diaxial elimination, forming a C-2,C-3 enol. -!- The product loses a second water molecule to form anthocyanidins. -!- When assayed in vitro, non-enzymic epimerization of the product can lead to formation of dihydroflavanols. -!- Thus when the substrate is leucocyanidin, a mixture of (+)-taxifolin and (+)-epitaxifolin are formed. -!- The enzyme can also oxidize the formed (+)-taxifolin to quercetin (cf. EC 1.14.20.6). -!- Formerly EC 1.14.11.19.

UniProtKB Entries (1)

Q96323
LDOX_ARATH
Arabidopsis thaliana
Leucoanthocyanidin dioxygenase

PDB Structure

PDB 2BRT
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Structural and Mechanistic Studies on Anthocyanidin Synthase Catalysed Oxidation of Flavanone Substrates: The Effect of C-2 Stereochemistry on Product Selectivity and Mechanism
Welford, R.W.D., Clifton, I.J., Turnbull, J.J., Wilson, S.C., Schofield, C.J.
Org.Biomol.Chem.