Hereditary Aberrancy in Growth of Some Strains Free

Abstract

SUMMARY: Two hundred strains of recently isolated from soil were tested for an antagonistic effect on a phage-resistant strain of the same species. Fifty-one strains gave a zone of inhibition on a lawn of the indicator strain. This effect was increased by a small dose of ultraviolet radiation which also caused 41 other strains to show an antagonistic effect. Sixteen strains which were completely lysed after u.v. irradiation also produced confluent lysis of the indicator strain. When grown in liquid media, these strains gave irregular growth curves owing to partial lysis during the exponential phase. Lysis was almost complete when such cultures were incubated after exposure to small doses of u.v. radiation. Lysis was always associated with accumulation of the antibacterial principal previously named ‘megacin’. Irregular growth in liquid media and production of megacin were strictly correlated. However, only 2 megacinogenic strains were lysogenic and liberated phage. Populations of megacinogenic strains were examined by replicaplating for the presence of non-megacinogenic mutants. Spore suspensions of 4 megacinogenic strains contained non-megacinogenic mutants in various proportions depending on the strain and the particular sample. Non-megacinogenic mutants could not be made to lyse by exposure to u.v. radiation; did not produce any antibacterial effects; and all showed normal patterns of growth in various liquid media. It is supposed that megacinogeny and aberrant growth, as well as inducibility by u.v. radiation, of some strains are governed by a single hereditary unit (gene). It cannot be decided at present whether or not this unit is a highly defective prophage.

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/content/journal/micro/10.1099/00221287-19-2-407
1958-10-01
2024-03-29
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References

  1. IvÁnovics G. 1955; Dissociation of Bacillus megaterium associated with the change of the cell wall antigenic structure. Acta microbiol. Acad. Sci., Hung 3:135
    [Google Scholar]
  2. IvÁnovics G., AlfÖldi L. 1954; A new antibacterial principle: megacine. Nature; London: 174465
    [Google Scholar]
  3. IvÁnovics G., AlfÖldi L. 1955; Observations on lysogenesis in Bacillus megaterium and on megacine, the antibacterial principle of this bacillus species. Acta microbiol. Acad. Sci., Hung 2:275
    [Google Scholar]
  4. IvÁnovics G., AlfÖldi L. 1957; Bacteriocinogenesis in Bacillus megaterium. J. gen. Microbiol 16:522
    [Google Scholar]
  5. IvÁnovics G., AlfÖldi L., Lovas B. 1957; Cultivation and electron microscopy of a bacteriocinogenic strain of Bacillus megaterium. Acta microbiol. Acad. Sci., Hung 4:295
    [Google Scholar]
  6. IvÁnovics G., AlfÖldi L., SzÉll A. 1957; Serological types of Bacillus mega- terium and their sensitivity to phages. Acta microbiol. Acad. Sd., Hung 4:333
    [Google Scholar]
  7. Leberberg J., Lederberg E.M. 1952; Replica plating and indirect selection of bacterial mutants. J. Bact 63:399
    [Google Scholar]
  8. Tarr H.L.A. 1932; The relation of the composition of the culture medium to the formation of endospores by aerobic bacilli. J. Hyg., Camb 32:535
    [Google Scholar]
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