‘Take-over’—an Unusual Selection Process in Steady-State Cultures of Free

Abstract

When the proportion of prototrophic revertants in a continuous culture of the tryptophan-requiring strain wp2 of was adjusted to exceed about 10, a large increase (‘take-over’) often occurred after a variable delay, the proportion becoming as high as 50% in some cases. The phenomenon appeared to be correlated with a selective advantage of revertants which became attached, with parent auxotrophs, to the wall of the culture tube. After some hours the film of growth on the wall was composed of approximately 10 bacteria. It was quite different from the massive ‘sticky’ growth sometimes encountered in continuous cultures of . The experimental observations of this ‘take-over’ are quantitatively consistent with a hypothesis of wall adsorption of rather rare and readily attached variant prototrophs.

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/content/journal/micro/10.1099/00221287-37-3-411
1964-12-01
2024-03-28
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References

  1. de Haan P. G. 1954; Genetic recombination of Escherichia coli b. (I). The transfer of the F agent to Escherichia coli b. Genetica 27:293
    [Google Scholar]
  2. Haas F. L., Doudney C. O. 1957; A relation of nucleic acid synthesis to radiation-induced mutation frequency in bacteria. Proc. nat. Acad. Sci., Wash. 43:871
    [Google Scholar]
  3. Jacob F., Wollman E. L. 1961; Sexuality and the Genetics of Bacteria. New York: Academic Press Inc;
    [Google Scholar]
  4. Munson R. J., Jeffery A. 1964; Reversion rate in continuous cultures of an Escherichia coli auxotroph exposed to gamma rays. J. gen. Microbiol. 35:191
    [Google Scholar]
  5. Munson R. J., Maclean F. I. 1961; The nature and radiation sensitivity of the long forms of Escherichia coli strain b/r. J. gen. Microbiol. 25:29
    [Google Scholar]
  6. Powell E. O. 1956; Growth rate and generation time of bacteria with special reference to continuous culture. J. gen. Microbiol. 15:492
    [Google Scholar]
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