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H E KUBITSCHEK

Publications and source records attributed to H E KUBITSCHEK.

13 recordsLinked to original sources
PubMed1964

MUTATION IN CONTINUOUS CULTURES. 3. MUTATIONAL RESPONSES IN ESCHERICHIA COLI.

Kubitschek, H. E. (Argonne National Laboratory, Argonne, Ill.), and Lynn A. Gustafson. Mutation in continuous cultures. III. Mutational responses in Escherichia coli. J. Bacteriol. 88:1595-1597. 1964.-In continuous cultures of Escherichia coli K-12-W6 in minimal media, the growth rate dependence of the rate of mutation to resistance to bacteriophage T(5) depended upon the nutrient factor used to limit growth. In glucose-limited cultures, caffeine-induced mutation rates were predominantly proportional to generation rate. However, in cultures limited with the required amino acid, methionine, mutation rates appeared to be independent of generation rate, both for caffeineinduced and for spontaneous mutation. These mutational responses agree with those found earlier in tryptophan auxotrophs of E. coli B, suggesting that constancy of mutation occurs when growth is limited with a required amino acid. Since these two kinds of strains differ in their control of ribonucleic acid (RNA) synthesis, these results show that the RNA-control locus does not affect the mutational response.

Caffeine↗
PubMed1960

The error hypothesis of mutation.

Accumulation of mutants in glucose-limited chemostats is proportional to growth rate, while in tryptophan-limited chemostats it is independent of growth rate. This behavior, which implies the failure of the error hypothesis, may be explainable on the basis of a unitary hypothesis: the results with glucose may be due to reversion or loss of latent mutants.

Genetics↗