Organization and Replication of the Genome

Abstract

As might be anticipated from the complexity of their architecture and polypeptide content, the poxviruses contain a large molecular weight genome. By direct visualization after spreading on protein films by the Kleinschmidt procedure or by physical-chemical determinations, it is evident that the genomes exist as double stranded linear DNA molecules about 45 to 60 µm long, (Fig. 11 A) (Randall et al., 1966; Hyde et al., 1967; Gafford and Randall, 1967; Gafford et al., 1978; Arif, 1976; Geshelin and Berns, 1974). A presumed detection of single stranded DNA within the virion (Pfau and McCrea, 1962a, b) has not been substantiated and this result could, conceivably, have been obtained artifactually as a consequence of the extraction method employed, which produces fragments of denatured DNA.