Transcription antitermination by bacteriophage lambda N gene product

摘要: Abstract In the presence of lambda N gene product, transcription originating at prophage p L promoter can extend beyond termination signals and into neighboring bacterial gal operon. Escherichia coli rho mutants, function is still required for to enter . The requirement in mutants abolished by deletion genome between 57.4 70.9 fractional lengths. These results suggest: 1. (1) Rho-independent sites lie operon lambda. 2. (2) Both Rho-dependent terminators are suppressed function. product must, therefore, be considered as a antitermination factor, rather than an antagonist Rho, previously suggested. Various DNA segments have been interposed their effect on escape synthesis studied. Lambda encoding 6 S transcript, which ends terminator, does not reduce synthesis. J-b2 region phage chromosome, however, completely blocks -promoted enzyme synthesis; block partially relieved rho15 mutation. introduction large lowers both + mutants. extent directly proportional efficiency suppression Nam mutation, suggesting that made excess.