Preliminary studies of crystals of poliovirus type I

Poliovirus contains 60 copies each of four coat protein subunits arranged on a T = 1 icosahedral surface. Crystals of the Mahoney and the Sabin strains of the type I serotype of polio have been obtained. Crystals of the Mahoney strain belong to the orthorhombic space group P2₁2₁2 with $\text{a = 324}\text{A}\text{?}\text{, b = 359}\text{A}\text{?}\text{, c = 381}\text{A}\text{?}$, contain $\text{1}\text{2}$ virus particle in the asymmetric unit, and diffract to at least 2.5 Å resolution. The crystals are apparently identical to those characterized by Finch & Klug (1959). Collection of three-dimensional X-ray diffraction data to 2.9 Å resolution is in progress.