[Topological model of bacteriophage-T4 DNA replication].

The structure and function of the DNA--membrane complex in E. coli cells infected with bacteriophage T4 was studied. The DNA--membrane complex was isolated from the cells pulse or uniformly labeled with 3H-thymidine, fractionated by detergent treatment and separated on a discontinuous sucrose gradient. The attachment of small DNA fragments to the plasma membrane was analysed. Replicating bacteriophage T4 DNA was reversibly associated with the cytoplasmic membrane in the wall/membrane adhesion zones of the envelope. In the adhesion zone the cell wall, cytoplasmic membrane, DNA, different replicative proteins, probably form the initiation complex resistant to sonication, DNAase and Triton-X-100. This association is probably reversible. The topological aspects of bacteriophage T4 DNA replication are discussed.