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Ambivalent rII mutants of phage T4

Benzer, Seymour and Champe, Sewell P. (1961) Ambivalent rII mutants of phage T4. Proceedings of the National Academy of Sciences of the United States of America, 47 (7). pp. 1025-1038. ISSN 0027-8424. PMCID PMC221320. doi:10.1073/pnas.47.7.1025.

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The rII mutants of phage T4 differ from the standard type in being inactive on strains of Escherichia coli lysogenic for phage X. While the mutants attach to the cells and inject their DNA, progeny fail to appear. In this paper it is shown that one or another subset of the rII mutants can become active as a result of modification of the host, either by mutation or by the action of 5-fluorouracil. The effects are characterized by extreme specificity, applying only to certain rII mutations at certain points within the two rII cistrons. The phenomenon resembles what has been called, in many other systems, "allele-specific suppression [1]," in which a mutation outside a genetic region controlling a particular function suppresses the effects of some of the mutations within the region. An advantage of the phage system is that a given genetic message, in the form of a phage mutant, can be readily inserted into different hosts. The stimulus for the present investigation derives from the possibility that modifications of the host affecting the expression of specific phage mutations might be a key to the detection of alterations in the components of the cellular system for translating genetic information.

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Additional Information:© 1961 by the National Academy of Sciences Communicated May 19, 1961 We are indebted to Mmes. Daine Auzins, Esther Braendlin, Nancy Carson, and Sheridan Green for able assistance with the experiments, and to Max Delbrück for his infallible moderating influence. This research has been supported by grants from the National Science Foundation, the National Institutes of Health, and a Postdoctoral Research Fellowship (S.P.C.) from the American Cancer Society.
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American Cancer SocietyUNSPECIFIED
Issue or Number:7
PubMed Central ID:PMC221320
Record Number:CaltechAUTHORS:BENpnas61b
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Official Citation:AMBIVALENT rII MUTANTS OF PHAGE T4 Seymour Benzer, Sewell P. Champe Proceedings of the National Academy of Sciences Jul 1961, 47 (7) 1025-1038; DOI: 10.1073/pnas.47.7.1025
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:6182
Deposited By: Archive Administrator
Deposited On:28 Nov 2006
Last Modified:08 Nov 2021 20:31

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