Subviral particles (Gu-subviral particles) containing DNA complexed with 20-25% of the protein found in complete virus particles could be isolated after treating purified vaccinia virions with 8 M guanidine-HCI, 1% Nonidet-P40, and 1% 2-mercaptoethanol. Electron microscopic examination of the Gu-subviral particles fixed with glutaraldehyde and formaldehyde, revealed spherical structures, 300-350 nm in diameter. DNA in combination with protein was observed to be further folded into globular structures, 200-600 Å in diameter on the surface of the particles. Analysis of the proteins in Gu-subviral particles by SDS-polyacrylamide gel electrophoresis showed that 10 polypeptides with molecular weights of 120K, 90K, 68K, 61K, 58K, 32K, 27K, 24K, 14.5K, and 10K were associated with the viral DNA. After dialysis, the particles could be shown to have retained, in part, the capacity to catalyze the synthesis of RNA in vitro.
ASJC Scopus subject areas