No abstract

A study has been made of human adenovirus type 6 (Ad 6) which belongs to the C subgroup of the nononcogenic adenoviruses. The buoyant density of the Ad 6 virions in CsCl gradient was 1.3545 +/- 0.0010 g/cm3. The DNA content determined from the buoyant density values and direct phosphorus analysis was 11.2 +/- 0.5 and 11.5 +/- 0.5 per cent, respectively. The S20,w0 and D20,w0 values for the Ad 6 virions were 795 +/- 18S and (3.255 +/- 0.035) X 10-8 cm2/s. The hydrodynamic parameters of the viral particle and its volume as well as the specific partial volume, the content and the molecular weight of the DNA have yielded a molecular weight of the virions of (203.6 +/- 10.0) X 10(6). The sedimentation constant and the intrinsic viscosity of the DNA have been found to be 32.7 +/- 0.7S and 93.5 +/- 5.0 dl/g, respectively. The molecular weight of the DNA found from these results is (23.4 +/- 0.8) X 10(6). The buoyant density of the Ad 6 DNA measured in CsCl and Cs2SO4 density gradients was 1.7128 +/- 0.0010 and 1.427 +/- 0.001 g/cm3, respectively. The GC content found from the buoyant density and the melting temperature (90.5 +/- 0.1 degrees C in 1 SSC and 75.0 +/- 0.1 degrees C in 0.1 SSC) was 52.6 +/- 1.0 per cent, that is, it is considerably lower than the GC content of 56-60 per cent which, according to the "Green's rule", should be typical of the DNAs of all the human adenoviruses of the subgroup C (30).

SUMMARYThe sedimentation constant of simian virus type 38 (SV-38) DNA was estimated to be 3I'6S. The intrinsic viscosity of DNA was on average 86"5 dl/g and the length of the molecule determined by electron microscopy was lo.6#m. The average mol. wt., as determined by sedimentation and viscometry, was 21.5 × IO6, which agreed well with the value derived from the length of the molecule (2I. 4 × IO 6) and with the value of 21-2 × 1o 6 determined by the relative electrophoretic mobility of the DNA fragments produced by restriction endonucleases EcoRI, SalI and BgIII.The buoyant density of the DNA in caesium chloride and caesium sulphate was I'7185 and 1.4295 g/ml respectively. The melting temperature of the DNA in I × SSC was 93"5 °C. The GC content calculated fromp and Tm values was 59"3 %.

No abstract

No abstract

SUMMARYDifferent methods of molecular hybridization were used to study DNA sequences of the highly oncogenic simian adenovirus SA7 (C8) present in the genomes of two transformed rat cell lines and in cells from three hamster tumours induced by adenovirus SA7. The entire DNA or the left-hand terminal SalI C fragment (19-5 ~ of the genome) were employed. All cell lines retained an intact left-hand region of the SA7 genome (0 to 12-4 map units). The blot hybridization technique failed to detect any site specificity of integration of SA7 DNA into the cell genome. In all cell lines the expression of the BglII D fragment (1.8 to l0 map units) of SA7 DNA was observed. As judged by the patterns of integration of virus sequences into the cell genome, the highly oncogenic simian adenovirus SA7 (C8) is similar to the non-oncogenic human adenoviruses of group C, and is different from the highly oncogenic human adenovirus type 12.

No abstract