3GKE

Crystal Structure of Dicamba Monooxygenase

Summary for 3GKE

• Entry DOI: 10.2210/pdb3gke/pdb
• Related: 3GL0 3GL2
• Descriptor: DdmC, FE2/S2 (INORGANIC) CLUSTER, FE (III) ION, ... (7 entities in total)
• Functional Keywords: rieske cluster, non-heme mononuclear iron, oxygenase, oxidoreductase
• Biological source: Stenotrophomonas maltophilia (Pseudomonas maltophilia)
• Total number of polymer chains: 3
• Total formula weight: 117391.02

Authors

Wilson, M.A.,Dumitru, R.,Jiang, W.Z.,Weeks, D.P. (deposition date: 2009-03-10, release date: 2009-07-21, Last modification date: 2024-02-21)

Primary citation

Dumitru, R.,Jiang, W.Z.,Weeks, D.P.,Wilson, M.A.
Crystal structure of dicamba monooxygenase: a Rieske nonheme oxygenase that catalyzes oxidative demethylation.
J.Mol.Biol., 392:498-510, 2009

PubMed Abstract: Dicamba (3,6-dichloro-2-methoxybenzoic acid) is a widely used herbicide that is efficiently degraded by soil microbes. These microbes use a novel Rieske nonheme oxygenase, dicamba monooxygenase (DMO), to catalyze the oxidative demethylation of dicamba to 3,6-dichlorosalicylic acid (DCSA) and formaldehyde. We have determined the crystal structures of DMO in the free state, bound to its substrate dicamba, and bound to the product DCSA at 2.10-1.75 A resolution. The structures show that the DMO active site uses a combination of extensive hydrogen bonding and steric interactions to correctly orient chlorinated, ortho-substituted benzoic-acid-like substrates for catalysis. Unlike other Rieske aromatic oxygenases, DMO oxygenates the exocyclic methyl group, rather than the aromatic ring, of its substrate. This first crystal structure of a Rieske demethylase shows that the Rieske oxygenase structural scaffold can be co-opted to perform varied types of reactions on xenobiotic substrates.

PubMed: 19616011
DOI: 10.1016/j.jmb.2009.07.021

Experimental method

X-RAY DIFFRACTION (1.75 Å)