Affiliation:
1. Department of Pharmacology, Yale University, New Haven, Connecticut 06510
Abstract
Evidence was obtained which indicates that the lethal effect of 5-iodouracil (IUra) on bacteriophage T4 is not due to a mutagenic process. T4
td
8
r
II (thymine requiring, rapid lysis) double mutants were constructed. Reversion of T4
td
8
r
II to
r
+
was measured. First, reversion by growth in the presence of the structural analogues chlorouracil (ClUra) and bromouracil (BrUra) did not correlate with their relative lethal effects (for mutagenesis: IUra ≤ ClUra ≤ BrUra; for lethality: ClUra < BrUra < IUra). Second, reversion frequencies of T4
td
8
r
II in infected cells increased linearly with time of growth in the presence of IUra, whereas the frequency of lethality was constant with time. Third, reversion frequencies increased markedly at low levels of IUra substitution, whereas lethal effects were apparent only with extensive IUra substitution. Fourth, the reversion frequency of the nonviable fraction of IUra-substituted T4
td
8
r
II (as examined by multiplicity reactivation) did not differ significantly from that of the viable IUra-substituted T4
td
8 fraction. If mutagenesis caused lethality, then the nonviable T4
td
8
r
II fraction should accumulate mutations and have a higher reversion frequency.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Pharmacology (medical),Pharmacology
Reference24 articles.
1. An immunological study of an enzyme made by phage containing 5-iodo-2'- deoxyuridine-substituted deoxyribonucleic acid;Aamodt L.;Biochem. Pharmacol.,1970
2. Adams M. H. 1959. Appendix p. 443-552. In Bacteriophages. John Wiley & Sons Inc. New York.
3. Fine structure of a genetic region in bacteriophage;Benzer S.;Proc. Natl. Acad. Sci. U.S.A.,1955
4. Comparison of the lethal effect of 5-iodouracil incorporated into bacteriophage T4 in the presence and absence of near-visible light;Byrd D. M.;Photochem. Photobiol.,1975
5. Multiplicity reactivation of 5-iodouracil-substituted, nonviable bacteriophage T4d8;Byrd D. M.;Antimicrob. Agents Chemother.,1975
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