Cyclic thymineless death significantly increases frequency of R-plasmid elimination.
نویسندگان
چکیده
Thymine starvation of Escherichia coli strain C600 thy (R46) eliminated the R plasmid at a frequency of 17%. This was increased fourfold, to 68%, after the same culture was subjected to an additional three cycles of growth followed by thymineless death.
منابع مشابه
R factor elimination during thymine starvation: effects of inhibition of protein synthesis and readdition of thymine.
R factor 1818 is shown to be eliminated from a thymineless strain of Escherichia coli J6-2 (R-1818) during thymine starvation. Readdition of thymine to the starved cultures produces a partial recovery in viable count but does not affect the proportion of R(-) cells. The R factor is not cured from exponential- or stationary-phase cultures which are starved of required amino acids as well as thym...
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Thymineless death was examined in Escherichia coli 15T(-) and recombinants of 15T(-) and E. coli K-12. Those strains that were very sensitive to thymine deprivation were also very sensitive to a variety of inducing agents (mitomycin C, ultraviolet light, hydroxyurea, and nalidixic acid). Those strains that were relatively resistant to thymineless death were also relatively resistant to the indu...
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In colon cancers induction of a thymineless state following inhibition of thymidylate synthase (TS) by 5-fluorouracil combined with leucovorin can initiate a cytotoxic response. Using a 5-fluorouracil-leucovorin-treated human colon carcinoma cell line (GC,Icl) and a clonally derived TS mutant, initiation events that dictate the onset of and commitment to thymineless death have been examined. In...
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متن کاملEnergy Requirement for Thymineless Death in Cells of Escherichia Coli.
Freifelder, David (University of California, Berkeley), and Ole Maaløe. Energy requirement for thymineless death in cells of Escherichia coli. J. Bacteriol. 88:987-990. 1964.-Thymineless death in thymine-requiring Escherichia coli is arrested immediately and reversibly by nitrogenation if the bacterial population is growing in a medium containing a carbon source that can only be metabolized aer...
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عنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 12 4 شماره
صفحات -
تاریخ انتشار 1977