3L4P

Crystal structure of the Aldehyde Dehydrogenase (a.k.a. AOR or MOP) of Desulfovibrio gigas covalently bound to [AsO3]-

Replaces:  1ZCS

Summary for 3L4P

• Entry DOI: 10.2210/pdb3l4p/pdb
• Related: 1DGJ 1SIJ 1VLB 3FAH 3FC4
• Descriptor: Aldehyde oxidoreductase, CALCIUM ION, FE2/S2 (INORGANIC) CLUSTER, ... (11 entities in total)
• Functional Keywords: molybdenum-containing enzymes, aldehyde oxidoreductase, xanthine oxidase family, reduced form, arsenite inhibition, 2fe-2s, fad, flavoprotein, iron, iron-sulfur, metal-binding, molybdenum, nad, oxidoreductase
• Biological source: Desulfovibrio gigas
• Total number of polymer chains: 1
• Total formula weight: 99187.50

Authors

Boer, D.R.,Romao, M.J. (deposition date: 2009-12-21, release date: 2010-02-16, Last modification date: 2023-11-01)

Primary citation

Thapper, A.,Boer, D.R.,Brondino, C.D.,Moura, J.J.,Romao, M.J.
Correlating EPR and X-ray structural analysis of arsenite-inhibited forms of aldehyde oxidoreductase.
J.Biol.Inorg.Chem., 12:353-366, 2007

PubMed Abstract: Two arsenite-inhibited forms of each of the aldehyde oxidoreductases from Desulfovibrio gigas and Desulfovibrio desulfuricans have been studied by X-ray crystallography and electron paramagnetic resonance (EPR) spectroscopy. The molybdenum site of these enzymes shows a distorted square-pyramidal geometry in which two ligands, a hydroxyl/water molecule (the catalytic labile site) and a sulfido ligand, have been shown to be essential for catalysis. Arsenite addition to active as-prepared enzyme or to a reduced desulfo form yields two different species called A and B, respectively, which show different Mo(V) EPR signals. Both EPR signals show strong hyperfine and quadrupolar couplings with an arsenic nucleus, which suggests that arsenic interacts with molybdenum through an equatorial ligand. X-ray data of single crystals prepared from EPR-active samples show in both inhibited forms that the arsenic atom interacts with the molybdenum ion through an oxygen atom at the catalytic labile site and that the sulfido ligand is no longer present. EPR and X-ray data indicate that the main difference between both species is an equatorial ligand to molybdenum which was determined to be an oxo ligand in species A and a hydroxyl/water ligand in species B. The conclusion that the sulfido ligand is not essential to determine the EPR properties in both Mo-As complexes is achieved through EPR measurements on a substantial number of randomly oriented chemically reduced crystals immediately followed by X-ray studies on one of those crystals. EPR saturation studies show that the electron transfer pathway, which is essential for catalysis, is not modified upon inhibition.

PubMed: 17139522
DOI: 10.1007/s00775-006-0191-9

Experimental method

X-RAY DIFFRACTION (1.45 Å)