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Phi-X-174 bacteriophage structural mutants which affect deoxyribonucleic acid synthesis.

J E Siegel·M Hayashi
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Abstract

Seven cistrons in phiX-174 were identified and one in particular was studied intensively: cistron A, which is assigned a protein in the mature phage. Amber mutants in this cistron synthesize a new deoxyribonucleic acid (DNA) form in addition to circular phage DNA upon infection of the restrictive host. This DNA is linear, non-infectious, and single-stranded; it is formed from the phage strand of replicative form phiX-174 DNA. These mutants produce two different defective particles in the restrictive host. One particle contains circular phage DNA but is not infectious; the other contains the new DNA form and is similar to the 70S particles found in wild-type phage lysates. The mutant A gene product acts independently of normal A protein upon mixed infection of the restrictive host with an A mutant and a mutant from any other cistron or wild type.

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BacteriophagesComplement Fixation TestsDNA, ViralGenesHybridization, GeneticMutationRadiometryThymidineTritiumViral ProteinsVirus CultivationJournal Article

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J E Siegel, M Hayashi. 1969. Phi-X-174 bacteriophage structural mutants which affect deoxyribonucleic acid synthesis.. https://doi.org/10.1128/jvi.4.4.400-407.1969

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