Crystallization and preliminary crystallographic analysis of a thermostable family 52 β-D-xylosidase from Geobacillus stearothermophilus T-6

β-D-Xylosidases (EC 3.2.1.37) are hemicellulases that hydrolyze short xylooligosaccharides into single xylose units. In this study, the first crystallization and preliminary X-ray analysis of a family 52 glycoside hydrolase, the β-D-xylosidase (XynB2) from Geobacillus stearothermophilus T-6, is described. XynB2 is a dimeric protein consisting of two identical subunits of 705 amino acids with a calculated molecular weight of 79 894 Da. XynB2 was crystallized by the hanging-drop vapour-diffusion method and the crystals were found to belong to space group P1, with unit-cell parameters a = 80.6, b = 97.5, c = 107.2 Å, α = 107.4, β = 98.2, γ = 106.6°. The native crystals diffracted X-rays to a resolution of 2.0 Å.