Replication of bacteriophage phiX-174 in a mutant of Escherichia coli defective in the dnaE gene.

Strains of E. coli bearing a temperature-sensitive mutation at the dnaE locus were unable to support growth of bacteriophage varphiX-174 at 43 degrees while permitting normal growth at 30 degrees . The dnaE gene product was implicated in all stages of varphiX-174 DNA replication. Differences were observed between a double mutant (pol A(-), dnaE(ts)) and a single mutant (pol A(+), dnaE(ts)) in the ability to synthesize parental replicating form and its subsequent replication. The implications of these observations are discussed in terms of the relationship between DNA polymerases-I and -III.