Isolation and properties of the DNA of African swine fever (ASF) virus.

African swine fever (ASF) virus was grown either in swine macrophages or in VERO cells and purified free of cell DNA. Virus DNA was isolated from virions as a molecule with a sedimentation coefficient of 60S and a contour of 58 +/- 3 mum. .these two values give a mol. wt. of 102 +/- 5 X 10(6) and 107 +/- 5 X 10(6), respectively, for the genome of ASF virus. Denatured DNA fragments from ASF virus reassociate with a C0t1/2 value of 0-60 +/- 0-05 MS, which compared with the corresponding value for T4 DNA gives for the molecular mass of ASF virus DNA a value of 102 +/- 8 X 10(6) daltons. Only virus DNA is synthesized ASF virus-infected swine macrophages.