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The sedimentation constant of simian virus type 38 (SV-38) DNA was estimated to be 31.6S. The intrinsic viscosity of DNA was on average 86.5 dl/g and the length of the molecule determined by electron microscopy was 10.6 µm. The average mol. wt., as determined by sedimentation and viscometry, was 21.5 × 106, which agreed well with the value derived from the length of the molecule (21.4 × 106) and with the value of 21.2 × 106 determined by the relative electrophoretic mobility of the DNA fragments produced by restriction endonucleases EcoR1, SalI and BglII.
The buoyant density of the DNA in caesium chloride and caesium sulphate was 1.7185 and 1.4295 g/ml respectively. The melting temperature of the DNA in 1 × SSC was 93.5 °C. The GC content calculated from ρ and Tm values was 59.3%.
BglII cleaves SV-38 DNA at three sites producing four fragments with mol. wt.: A, 9.3 × 106; B, 5.6 × 106; C, 3.3 × 106; and D, 2.9 × 106. After treatment with EcoR1 and SalI, SV-38 DNA is cleaved into five and six fragments respectively, with mol. wt. for EcoR1 fragments: A, 8.2 × 106; B, 6.5 × 106; C, 4.0 × 106; D, 1.27 × 106; and E, 1.07 × 106, and for SalI fragments: A, 6.5 × 106; B, 5.4 × 106; C, 4.2 × 106; D, 2.8 × 106; E, 2.5 × 106 and F, 0.25 × 106. The sequence of fragments within the SV-38 DNA molecules for BglII was deduced to be BDCA, and for EcoR1 - BCEAD.