1GP6

Anthocyanidin synthase from Arabidopsis thaliana complexed with trans-dihydroquercetin (with 30 min exposure to O2)

Summary for 1GP6

• Entry DOI: 10.2210/pdb1gp6/pdb
• Descriptor: LEUCOANTHOCYANIDIN DIOXYGENASE, SUCCINIC ACID, 2-(N-MORPHOLINO)-ETHANESULFONIC ACID, ... (7 entities in total)
• Functional Keywords: oxidoreductase, oxygenase, 2-oxoglutarate dependent dioxygenase, flavonoid biosynthesis
• Biological source: ARABIDOPSIS THALIANA (MOUSE-EAR CRESS)
• Total number of polymer chains: 1
• Total formula weight: 41622.25

Authors

Wilmouth, R.C.,Turnbull, J.J.,Welford, R.W.D.,Clifton, I.J.,Prescott, A.G.,Schofield, C.J. (deposition date: 2001-10-30, release date: 2002-02-21, Last modification date: 2023-12-13)

Primary citation

Wilmouth, R.C.,Turnbull, J.J.,Welford, R.W.D.,Clifton, I.J.,Prescott, A.G.,Schofield, C.J.
Structure and Mechanism of Anthocyanidin Synthase from Arabidopsis Thaliana.
Structure, 10:93-, 2002

PubMed Abstract: Flavonoids are common colorants in plants and have long-established biomedicinal properties. Anthocyanidin synthase (ANS), a 2-oxoglutarate iron-dependent oxygenase, catalyzes the penultimate step in the biosynthesis of the anthocyanin class of flavonoids. The crystal structure of ANS reveals a multicomponent active site containing metal, cosubstrate, and two molecules of a substrate analog (dihydroquercetin). An additional structure obtained after 30 min exposure to dioxygen is consistent with the oxidation of the dihydroquercetin to quercetin and the concomitant decarboxylation of 2-oxoglutarate to succinate. Together with in vitro studies, the crystal structures suggest a mechanism for ANS-catalyzed anthocyanidin formation from the natural leucoanthocyanidin substrates involving stereoselective C-3 hydroxylation. The structure of ANS provides a template for the ubiquitous family of plant nonhaem oxygenases for future engineering and inhibition studies.

PubMed: 11796114
DOI: 10.1016/S0969-2126(01)00695-5

Experimental method

X-RAY DIFFRACTION (1.75 Å)