Authors describe in this paper the isolation and characterization of a class of mutations, designated puq, that allow phage λ to grow better under conditions that limit the synthesis of the phage Q gene product. These mutations were located between phage genes P and Q, a region of the λ chromosome containing two gene N-independent mutations, nin5 and byp, that we also show to be puq mutations. Whereas the puq-3 and puq-16 mutations probably map under the nin5 deletion, the byp mutation maps between this deletion and the Qλ-Qphi80 crossover point. These mutations likely act by increasing the synthesis of the Q gene product. We demonstrate that the clear-plaque phenotype and reduced lysogenization frequency of byp mutants depend on increased Q gene activity. The significance of these results in understanding how transcription proceeds through the P-Q region of the λ genome is discussed.
All Science Journal Classification (ASJC) codes
- Insect Science