Radiation-induced Instabilities in Streptomyces Free

Abstract

SUMMARY: A variety of heritable changes affecting colony morphology and colour are induced in a sp. by exposure of the spores to ultraviolet and gamma rays. Most of the changes are associated with instabilities which give rise to further variation during colony growth and spore formation. The instabilities persist indefinitely in most lines of descent and give rise to characteristic proportions of new variant types each having its own pattern of instability. The ultraviolet dose/effect curve shows the familiar peak and decline found for mutations in many other organisms. The present changes, however, differ from the gene mutations previously studied in that they can be induced with much greater frequencies (30-60% of the colonies being affected), and that gamma rays are as effective or more so than ultraviolet irradiation. This suggests that the initial changes, and perhaps subsequent ones as well, might be more of the nature of the chromosomal rearrangements, rather than of the gene mutations, of higher organisms. Similar instabilities arise spontaneously but with a much lower frequency.

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/content/journal/micro/10.1099/00221287-9-1-30
1953-08-01
2024-03-29
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References

  1. Bryson V., Prytz B., Cuneo H., Yongen E., Raymond C. 1950; Morphological and biochemical analysis of resistant bacteria. Annu. Rep. Biol. Lab. Cold Spring Harbor20
    [Google Scholar]
  2. Kelner A. 1948; Mutation in Streptomyces flaveolus induced by X-rays and ultraviolet light. J. Bact. 56:457
    [Google Scholar]
  3. Kelner A. 1949; Studies on the genetics of antibiotic formation: the induction of antibiotic-forming mutants in Actinomycetes. . J. Bact. 57:73
    [Google Scholar]
  4. Klieneberger-Nobel E. 1947; The life cycle of sporing actinomyces as revealed by a study of their structure and septation. J. gen. Microbiol. 1:22
    [Google Scholar]
  5. McClintock B. 1951; Chromosome organization and genic expression. Cold Spr. Harb. Sym. quant. Biol. 16:13
    [Google Scholar]
  6. Newcombe H.B. 1951; Sectoring in colonies from irradiated cells of Escherichia coli. . Genetics 36:570
    [Google Scholar]
  7. Newcombe H.B. 1953; The delayed appearance of radiation induced genetic change in bacteria. Genetics 38:134
    [Google Scholar]
  8. Witkin E. 1951a; Nuclear segregation and delayed expression of induced mutations in Escherichia coli. . Genetics 36:583
    [Google Scholar]
  9. Witkin E. 1951b; Nuclear segregation and delayed appearance of induced mutants in Escherichia coli. . Cold Spr. Harb. Sym. quant. Biol. 16:357
    [Google Scholar]
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