Crystallization and preliminary X-ray diffraction analysis of O-acetylserine sulfhydrylase from Aeropyrum pernix K1

Crystals of O-acetylserine sulfhydrylase from Aeropyrum pernix K1 were obtained by the hanging-drop vapour-diffusion method at 298 K. An X-ray diffraction data set was collected to 2.25 A resolution at 100 K. The crystal belonged to space group P42(1)2, P4(1)2(1)2, P4(2)2(1)2 or P4(3)2(1)2. The unit-cell parameters were a = b = 74.5, c = 276.0 A. The presence of two subunits of the enzyme per asymmetric unit gives a crystal Volume per protein mass (V(M)) of 2.28 A(3) Da(-1) and a solvent content of 46%(v/v).