论文部分内容阅读
Spontaneous streptomycin-dependent mutants (Str~DA) were isolared from Escherichia coli C600. OnC600 Str~D, the lytic growth of phage λ Nam and λcI857 was inhibited. After E. coli lysogenic strain1.1485 (λcI857) mutated to Str~DA, induction of λ was decreased greatly. On Str~DA of E. coli strainsC600 and 1.1485 (λcI857), the plating efficiencies and burst sizes of phage T4 and T7 remained nor-mal. Since Str~DA is a mutation in the structural gene for ribosomal protein S12, the results obtained inthe present study suggest that ribosomes of the Str~DA mutants inhibit the Iytic growth of λ phage. The possibility that Str~DA ribosomes inhibit the expression of λ N gene is discussed based on thecomparison of the genetic background of λcI857 and λNam.