Cloned bacteriophage phi X174 DNA sequence interferes with synthesis of the complementary strand of infecting bacteriophage phi X174.

AUTOR(ES)

van der Avoort, H G

RESUMO

The insertion of a particular phi X DNA sequence in the plasmid pACYC177 strongly decreased the capacity of Escherichia coli cells containing such a plasmid to propagate bacteriophage phi X174. The smallest DNA sequence tested that showed the effect was the HindII fragment R4. This fragment does not code for a complete protein. It contains the sequence specifying the C-terminal part of the gene H protein and the N-terminal part of the gene A protein, as well as the noncoding region between these genes. Analysis of cells that contain plasmids with the "reduction sequence" showed that (i) the adsorption of the phages to the host cells is normal, (ii) in a single infection cycle much less phage is formed, (iii) only 10% of the infecting viral single-stranded DNA is converted to double-stranded replicative-form DNA, and (iv) less progeny replicative form DNA is synthesized. The reduction process is phi X174 specific, since the growth of the related G4 and St-1 phages was not affected in these cells. The effect of the recombinant plasmids on infecting phage DNA shows similarity to the process of superinfection exclusion.

Documentos Relacionados

• Mechanism of replication of bacteriophage phi X174 XIX. Initiation of phi X174 viral strand DNA synthesis at internal sites on the genome.
• DNA synthesis in Escherichia coli cells infected with gene H mutants of bacteriophage phi X174.
• Role of DNA gyrase subunits in synthesis of bacteriophage phi X174 viral DNA.
• Initiation and termination of the bacteriophage phi X174 rolling circle DNA replication in vivo: packaging of plasmid single-stranded DNA into bacteriophage phi X174 coats.
• In vitro synthesis of bacteriophage phi X174 by purified components.