Characterization of the genome of Herpesvirus sylvilagus

The genome of Herpesvirus sylvilagus, a gamma herpesvirus capable of inducing a lymphoproliferative disease in cottontail rabbits, was analyzed with respect to its infectivity, density in cesium chloride isopycnic gradients, and molecular weight. The buoyant density of virus DNA in cesium chloride was 1.710 g/cm3. Sucrose gradient centrifugation showed virus DNA to be 86.08 megadaltons (129.25 kilobase pairs). The restriction endonucleases EcoRI, XhoI, SstII, and BglI cleaved the virus DNA into 8, 7, 23, and 13 major fragments ranging from 38.32 to 0.53 kilobase pairs, respectively. The size of the virus DNA as determined from the restriction endonuclease analysis was 72.59 megadaltons (108.89 kilobase pairs). The average size of H. sylvilagus DNA, determined from electron microscopic observations, was 78.06 megadaltons (117.08 kilobase pairs).