Cloning of the immunity repressor determinant of bacteriophage P2 in the pBR322 plasmid

✍ Scribed by Westöö, Anna ;Ljungquist, Elisabeth

• Publisher: Springer
• Year: 1980
• Tongue: English
• Weight: 761 KB
• Volume: 178
• Category: Article
• ISSN: 0026-8925
• DOI: 10.1007/bf00267218

✦ Synopsis

Through in vitro recombination of DNA restriction fragments, we have constructed a plasmid, which expressed in vivo the immunity repressor gene (C) of bacteriophage P2. A bacterial strain carrying such a plasmid showed a high level of P2 specific immunity. It was lysogenized normally by an infecting P2, but the frequency of spontaneous phage production was reduced about 10(4) fold as compared to a normal P2 lysogen. Satellite phage P4, known to derepress P2 lysogens, was unable to derepress the plasmid-carrying lysogenic strain so to allow growth of coinfecting P2. Phage P4 multiplied on the plasmid-carrying, P2-lysogenic strain, but due to a prolonged latent period failed to form plaques on this strain.