8IN2

4,5-DOPA-extradiol-dioxygenase from Beta vulgaris

Summary for 8IN2

• Entry DOI: 10.2210/pdb8in2/pdb
• Descriptor: 4,5-DOPA dioxygenase extradiol, FE (III) ION (3 entities in total)
• Functional Keywords: dopa, dioxygenase, betalains, oxidoreductase
• Biological source: Beta vulgaris
• Total number of polymer chains: 2
• Total formula weight: 61556.64

Authors

Chiang, C.C.,Hsu, C.H. (deposition date: 2023-03-08, release date: 2024-04-24, Last modification date: 2025-05-07)

Primary citation

Chiang, C.C.,Lu, Y.J.,Liu, J.W.,Lin, S.W.,Chou, C.C.,Lin, C.H.,Chien, I.W.,Hsu, C.H.
Structural Insights into 4,5-DOPA Extradiol Dioxygenase from Beta vulgaris : Unraveling the Key Step in Versatile Betalain Biosynthesis.
J.Agric.Food Chem., 73:6785-6794, 2025

PubMed Abstract: Betalains, a group of pigments widely distributed in various plants, are extensively applied in the food, beverage, and medicinal industries. The biosynthesis of betalains involves the enzymatic action of 4,5-DOPA-dioxygenase, which catalyzes the key ring-opening reaction of DOPA to produce betalamic acid, a crucial intermediate in the pathway. The crystal structure of a 4,5-DOPA-dioxygenase from (BvDOD) was determined in this study. The structural analysis revealed that BvDOD exhibited a structural fold similar to that of other members of the extradiol dioxygenase family. Moreover, the Fe-ligand residues His15, His53, and His229 indicated the enzyme's reliance on nonheme iron for catalyzing the ring-opening reaction. Molecular docking and mutational analysis identified two conserved residues, His119 and His175, in the active site essential for the catalytic reaction. In addition, Thr17, Asp254, and Tyr260 contributed to properly positioning the substrate in the active site. This study has provided structural insights into substrate recognition and catalytic mechanisms of BvDOD, which can be applied to develop enzymes for improved betalain production.

PubMed: 40055856
DOI: 10.1021/acs.jafc.4c09501

Experimental method

X-RAY DIFFRACTION (3.08 Å)