Leucocyanidin oxygenase

In enzymology, a leucocyanidin oxygenase (EC 1.14.11.19) is an enzyme that catalyzes the chemical reaction

leucocyanidin + 2-oxoglutarate + O₂ ${\displaystyle \rightleftharpoons }$ cis- and trans-dihydroquercetins + succinate + CO₂ + 2 H₂O

leucocyanidin oxygenase
Identifiers
EC no.	1.14.11.19
CAS no.	180984-01-4
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / QuickGO
Search PMC articles PubMed articles NCBI proteins

The 3 substrates of this enzyme are leucocyanidin, 2-oxoglutarate, and O₂, whereas its 5 products are cis-dihydroquercetin, trans-dihydroquercetin, succinate, CO₂, and H₂O.

This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with 2-oxoglutarate as one donor, and incorporation of one atom o oxygen into each donor. The systematic name of this enzyme class is leucocyanidin,2-oxoglutarate:oxygen oxidoreductase. This enzyme is also called leucoanthocyanidin dioxygenase (LDOX) or anthocyanidin synthase (ANS). This enzyme participates in flavonoid biosynthesis.

In a broader way, leucocyanidin oxygenase uses flavan-3,4-diols (leucoanthocyanidins) to produce 3-hydroxyanthocyanidins.^[1] The gene encoding the enzyme (PpLDOX) has been identified in peach^[2] and expression has been studied in Vitis vinifera.^[3]

Structural studies

As of late 2007, only one structure, in Arabidopsis thaliana, has been solved for this class of enzymes, with the PDB accession code 2BRT.