Crystallization and preliminary X-ray crystallographic analysis of the unusual ferritin from Listeria innocua

Single crystals of ferritin extracted from Listeria innocua have been obtained by the vapour-diffusion method using PEG 1000 as precipitant. The crystals are orthorhombic, space group P2₁2₁2₁, with unit-cell dimensions a = 87.7, b = 137.5, c = 173.1 Å. The crystals diffract to 2.9 Å resolution on a rotating-anode X-ray source and to 2.35 Å resolution on a synchrotron X-ray source. The asymmetric unit contains one molecule formed by 12 subunits, corresponding to a packing density of 2.41 Å³ Da^-1