SUBUNIT COMPOSITION, CRYSTALLIZATION AND PRELIMINARY CRYSTALLOGRAPHIC STUDIES OF THE DESULFOVIBRIO-GIGAS ALDEHYDE OXIDOREDUCTASE CONTAINING MOLYBDENUM AND [2FE-2S] CENTERS

The Desulfovibrio gigas aldehyde oxidoreductase contains molybdenum bound to a pterin cofactor and [2Fe-2S] centers. The enzyme was characterized by SDS/PAGE, gel-filtration and analytical ultracentrifugation experiments. It was crystallized at 4-degrees-C, pH 7.2, using isopropanol and MgCl2 as precipitants. The crystals diffract beyond 0.3-nm (3.0-angstrom) resolution and belong to space group P6(1)22 or its enantiomorph, with cell dimensions a = b = 14.45 nm and c = 16.32 nm. There is one subunit/asymmetric unit which gives a packing density of 2.5 x 10(-3) nm3/Da (2.5 angstrom3/Da), consistent with the experimental crystal density, rho = 1.14 g/cm3. One dimer (approximately 2 x 100 kDa) is located on a crystallographic twofold axis.