title: Virion-associated RNA polymerase required for bacteriophage N4 development.
abstract: Escherichia coli phage N4 transcription is resistant to rifampicin, an inhibitor of the host RNA polymerase, even when the drug is added prior to infection. A rifampicin-resistant RNA polymerase has been detected in disrupted N4 virions. This enzyme shows a requirement for the four ribonucleoside 5'-triphosphates and exogenous denatured DNA. With denatured N4 DNA, the preferred template, transcription is asymmetric. The virion RNA polymerase apparently is necessary for phage development because a conditional lethal N4 mutant shows temperature-sensitive RNA synthesis in vivo as well as a temperature-sensitive RNA polymerase in disrupted virions.
mesh_terms: D001667:Binding, Competitive; D002701:Chloramphenicol / Q000494:pharmacology; D003090:Coliphages / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D007700:Kinetics; D009693:Nucleic Acid Hybridization; D013698:Templates, Genetic; D014158:Transcription, Genetic / Q000187:drug effects; D014779:Virus Replication
chemical_list: D002701:Chloramphenicol; D012321:DNA-Directed RNA Polymerases