Biochemical and biophysical characteristics of vesicular exanthema virus and the viral ribonucleic acid

Summary

The properties of three strains of VEV have been examined in an attempt to define its place in the classification of animal viruses. Each strain grew to high titre in a pig kidney cell line, IB-RS-2, was resistant to lipid solvents and pH 5 and could be purified by precipitation with ammonium sulphate, differential ultracentrifugation, detergent treatment and sedimentation in a sucrose gradient. The purified viruses had sedimentation coefficients in sucrose gradients of 160–170S and densities in caesium chloride ranging from 1.370 to 1.377 g/ml. In the electron microscope the 35–40 mμ particles had an appearance very similar to that described for the feline picornaviruses. Infectious RNA was obtained from each of the strains by extraction with 1% sodium deoxycholate and phenol. The infectivity of the RNA was destroyed by trace amounts of ribonuclease, indicating that the RNA is single-stranded. Labelled RNA prepared from³²P-virus sedimented in a sucrose gradient at 35–38S and was disrupted into slowly sedimenting molecules by incubating with 0.01 μg ribonuclease per ml prior to centrifugation. The percentage distribution of³²P in the four nucleotides was adenylic acid 29.0: cytidylic acid 25.1; guanylic acid 20.6; uridylic acid 25.3.