Crystallization and preliminary X-ray analysis of an alditol oxidase from Streptomyces coelicolor A3(2).

Alditol oxidase is a 45 kDa enzyme containing a covalently bound FAD cofactor. This oxidase efficiently oxidizes a range of alditols to the corresponding aldoses. Owing to its substrate range and regioselectivity, this enzyme is an interesting candidate for biotechnological applications. Crystals of alditol oxidase from Streptomyces coelicolor A3(2) were obtained by the hanging-drop vapour-diffusion method and diffracted to 1.1 A resolution. The crystals belong to space group C2, with unit-cell parameters a = 107, b = 68, c = 58 A, beta = 94 degrees. Crystals of seleno-L-methionine-labelled alditol oxidase were obtained after seeding the crystallization drops with native microcrystals and showed a diffraction limit of 2.4 A.