Replication of Bacteriophage T7 DNA by Purified Proteins
This extract was created in the absence of an abstract.
Excerpt
Bacteriophage T7 provides a system for understanding the enzymatic and molecular mechanisms involved in the replication of a linear, duplex DNA molecule. Each T7 particle contains an entirely double-stranded DNA molecule, each strand consisting of an uninterrupted sequence of 40,000 nucleotides (Fig. 1a). The DNA molecules isolated from T7, like those from T-even phages, contain a terminal repetition but, unlike the circularly permuted collection isolated from T-even phages, they form a unique collection of sequences (for reviews, see Thomas 1966; Studier 1972).
Considerable information is available concerning the mechanism of T7 DNA replication in vivo. At least in the early stages of infection, T7 DNA replicates as a linear monomer (Wolfson et al. 1972; Dressier et al. 1972; Wolfson and Dressier 1972), replication being initiated at a site 17% from the genetic left end of the linear T7 genome and proceeding bidirectionally (Fig. 1b). During T7 DNA replication, a major...
