Mechanism of viral replication. I. Structure of replication complexes of R17 bacteriophage

The replication of R17 bacteriophage in Escherichia coli MRE-600 cells was investigated using a new electron microscopic technique. The structures of replicating ribonucleoprotein complexes, as well as of purified replicative intermediate and replicative form, were studied. These structures are identical to those predicted by the model of Weissmann et al. (1968). From this it may be concluded that replication proceeds through essentially single-stranded inter-mediates and that double-stranded structures are either by-products or artifacts.