1887

Abstract

SUMMARY: In addition to R outgrowths, strains of growing on a carbohydrate-free medium also formed smooth secondary colonies situated on the primary colonies. These secondary colonies arose after about 6 days of incubation and were of two types: when centrally situated they formed papillae; when near the margin of the mother colony they often spilt over and formed fan-shaped outgrowths adjacent to the parent colony. Cultures of several different species of were examined; secondary colony formation was confined almost exclusively to strains of The fan-shaped outgrowths were pure cultures of organisms possessing a shorter generation time than those comprising the mother colony. An inverse relationship existed on crowded and sparsely inoculated plates between numbers of papillae and fan-shaped outgrowths/colony observed. The distribution of colonies bearing different numbers of secondary colonies did not follow a Poisson distribution; the random origin of fast-growing variants could not be established. On subculture the fast-growing variants produced colonies with a slightly different morphology from that of the wild-types. This difference was stable and persisted through numerous subcultures. In the presence of small quantities of fermentable carbohydrates secondary colony formation was not observed and this possibly explains how the wild type competes successfully with fast-growing variants in natural environments.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-29-2-291
1962-10-01
2024-03-28
Loading full text...

Full text loading...

/deliver/fulltext/micro/29/2/mic-29-2-291.html?itemId=/content/journal/micro/10.1099/00221287-29-2-291&mimeType=html&fmt=ahah

References

  1. Coetzee J. N. 1959; The late lactose-fermenting property of Shigella sonnet. S. Afr. J
    [Google Scholar]
  2. Lab. clin. Med. 5:170
    [Google Scholar]
  3. Coetzee J. N., de Klerk H. C., Sacks T. G. 1960; Host range of lactobacillus bacteriophages. Nature, Lond 187:348
    [Google Scholar]
  4. Coetzee J. N., Sacks T. G. 1960a; The late sucrose fermenting property of Proteus mirabilis. S. Afr. J. Lab. clin. Med 6:49
    [Google Scholar]
  5. Coetzee J. N., Sacks T. G. 1960b; Morphological variants of Proteus hauseri. J. gen. Microbiol 23:209
    [Google Scholar]
  6. de Klerk H. C., Coetzee J. N. 1962; The S–R variation in Lactobacillus casei. J. gen. Microbiol 27:155
    [Google Scholar]
  7. Mason M. Ms 1935; A comparison of maximal growth rates of various bacteria under optimal conditions. J. Bact 29:103
    [Google Scholar]
  8. Moser H. 1955 Carnegie Inst. (Wash.), Yearbook no 54: p 231
    [Google Scholar]
  9. Novick A., Szilard L. 1950; Experiments with the chemostat on spontaneous mutations of bacteria. Proc. not. Acad. Sci., Wash 36:708
    [Google Scholar]
  10. Rogosa M., Franklin J. G., Perry K. D. 1961; Correlation of the vitamin requirements with cultural and chemical characters of Lactobacillus spp. J. gen. Microbiol 25:473
    [Google Scholar]
  11. Rogosa M., Wiseman R. F., Mitchell J. A., Disraely M. N., Beaman A. J. 1953 Species differentiation of oral lactobacilli from man including descriptions of Lactobacillus salivarius nov.spec. and Lactobacillus cellobiosus nov.spec. J. Bact 65:681
    [Google Scholar]
  12. Ryan F. J., Schwartz M., Fried P. 1955; The direct enumeration of spontaneous and induced mutations in bacteria. J. Bact 69:552
    [Google Scholar]
  13. Shah K. K., Iyer V. N. 1960; Secondary colony formation by Bacillus subtilis on eosine methylene-blue agar. J. Bact 81:887
    [Google Scholar]
  14. Wheater D. M. 1955; The characteristics of Lactobacillus acidophilus and Lactobacillus bulgaricus. J. gen. Microbiol 12:123
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-29-2-291
Loading
/content/journal/micro/10.1099/00221287-29-2-291
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error