Antonie van Leeuwenhoek

, Volume 73, Issue 3, pp 255–261

Response of Azospirillum brasilense Cd to Sodium Chloride Stress

  • Viviana Rivarola
  • Stella Castro
  • Gladys Mori
  • Edgardo Jofré
  • Adriana Fabra
  • Rosana Garnica
  • Héctor Balegno
Article

DOI: 10.1023/A:1001053414777

Cite this article as:
Rivarola, V., Castro, S., Mori, G. et al. Antonie Van Leeuwenhoek (1998) 73: 255. doi:10.1023/A:1001053414777

Abstract

Growth of Azospirillum brasilense Cd in the presence of different NaCl concentrations showed that it tolerates up to 200 mM NaCl in the medium, without appreciable decline in growth rate. At 300 mM NaCl, a decrease of 66% in growth was observed at 24 h of culture. At 48 h of culture, bacteria in the presence of 300 mM NaCl reached the maximum optical density value that was attained at 12 h by control cultures. This investigation was designed to elucidate the effect of saline stress on Azospirillum brasilense Cd and the physiologic mechanism involved in its possible salinity tolerance. For this reason, studies of other osmolytes, as well as of putrescine metabolism and protein patterns were done with bacteria grown with this NaCl concentration in the medium, at 24 and at 48 hours. A. brasilense responded to saline stress elevating the intracellular concentration of glutamate at 24 h, and of K+at 48 h. Glucan pattern, putrescine metabolism, and total and periplasmic protein patterns of the treated group showed several changes with respect to the control. In spite of the several cellular functions affected by saline stress, the results imply that A. brasilense Cd shows salinity tolerance in these experimental conditions.

AzospirillumbacteriaglucansglutamateK+PGPRpolyaminessaline stress

Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Viviana Rivarola
    • 1
  • Stella Castro
    • 1
  • Gladys Mori
    • 1
  • Edgardo Jofré
    • 1
  • Adriana Fabra
    • 1
  • Rosana Garnica
    • 1
  • Héctor Balegno
    • 1
  1. 1.Facultad de Ciencias Exactas, Físico-Químicas y NaturalesUniversidad Nacional de Río CuartoCuarto-CórdobaArgentina