title: Streptomycin-resistant Escherichia coli mutant temperature sensitive for the production of Qbeta-infective particles.
abstract: A streptomycin-resistant Escherichia coli mutant has been isolated that is temperature sensitive for Qbeta phage, but not for the group I RNA phages f2, MS2, and R17. The growth of Qbeta in the mutant at the nonpermissive temperature (42 degrees C) results in the release of a near-normal burst of noninfectious particles that cosediment with Qbeta in a sucrose gradient. It is assumed that the mutant is defective at elevated temperatures in the suppression of nonsense codons, thereby producing Qbeta-like particles which are noninfectious because of the lack of the read-through protein A1.
mesh_terms: D003090:Coliphages / Q000254:growth & development* / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects; D008242:Lysogeny; D009154:Mutation; D012367:RNA, Viral / Q000096:biosynthesis; D013307:Streptomycin / Q000494:pharmacology; D013696:Temperature; D014779:Virus Replication
chemical_list: D012367:RNA, Viral; D013307:Streptomycin