1887

Abstract

SUMMARY: The turbidity of suspensions of various Gram-negative bacteria is affected by the tonicity of the suspending medium. The light extinction of the suspension increases in a nearly exponential fashion with the solute concentration and approaches a maximum at concentrations close to 0·15-NaCl. The maximal optical response to tonicity changes varies widely in different bacterial species, ranging from 30 to 140 % increase in light extinction as compared with the turbidity of the suspension in distilled water. The turbidity changes seem to depend on the viability of the bacterial cells as they cannot be elicited in bacteria killed by various procedures. The influence of the described phenomenon on the determination of bacterial cell concentration by the customary turbidimetric methods is discussed and its application for the estimation of the number of viable cells is suggested.

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/content/journal/micro/10.1099/00221287-14-1-69
1956-02-01
2024-04-24
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References

  1. Brudny V. 1908 Zbl. Bakt. (2.Abt.) 21:62 Cited after Knaysi, G. (1951). Elements of Bacterial Cytology, p. 347. Ithaca, New York:: Comstock Publishing Co. Inc.;
    [Google Scholar]
  2. Burke V. 1922; Notes on the Gram stain with description of a new method. J. Bact. 7:159
    [Google Scholar]
  3. Colländer R. 1937; The permeability of plant protoplasts to non-electrolytes. Trans. Faraday Soc. 33:985
    [Google Scholar]
  4. Danielli J.F. 1952 The Permeability of Natural Membranes. Cambridge University Press.:
    [Google Scholar]
  5. Eisenberg P. 1910 Zbl. Bakt. (1.Abt. Orig.) 56183 Knaysi G. cited after 1951 Elements of Bacterial Cytology, p. 349 Ithaca, New York:: Comstock Publishing Co. Inc.;
    [Google Scholar]
  6. Mager J., Kindler S.H., Grossowicz N. 1954; Nutritional studies with Clostridium parabotulinum Type A. J. gen. Microbiol. 10:130
    [Google Scholar]
  7. Mager J., Traub A., Grossowicz N. 1954; Cultivation of Pasteurella tularensisin chemically defined media: effect of buffers and spermine. Nature; Lond.: 174747
    [Google Scholar]
  8. Winslow C.-E.A., Falk I.S. 1923; Studies on salt action. IX. The additive and antagonistic effects of sodium and calcium chlorides upon the validity of. Bact. coli. J. Bact. 8:237
    [Google Scholar]
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