GATC sites might regulate virulence of Salmonella typhimurium

Abstract number: P1302

Chatti A., Landoulsi A.

Background and Objectives: Pathogenesis of Salmonellosis depends upon a large number of factors controlled by an array of genes that synergise into the actual virulence of Salmonella. A study was undertaken to observe the effect of dam and/or seqA on the virulence and stress response of Salmonella typhimurium.

Methods: All experiments described in this paper were carried out with Salmonella enterica serovar Typhimurium strain SL1344, LT2, and their isogenic mutants dam- and seqA-, respectively. For the virulence test, we are used LD50, competitive index (CI) and bacterial enumeration from target organs such as liver and spleen. For the study of the effect of dam or seqA mutation on the stress response, we have chosen to study response of these mutants toward bile, acidity, oxygen peroxide and antimicrobial peptides were tested.

Results: Our results show that dam or mutation attenuates Salmonella virulence either after intraperitoneal or oral infection. LD50, CI and enumeration of these mutants in liver and spleen prove a significantly decrease of virulence. On the other hand, in our work we are demonstrating that dam and seqA gene might control Salmonella typhimurium stress response (acid, bile, H2O2 and antimicrobial peptide).

Conclusion: Findings indicated that the dam and seqA genes may regulate virulence and stress response. We suggest that GATC distribution among DNA can regulate virulence and stress response of Salmonella typhimurium.

Session Details

Date: 19/04/2008
Time: 00:00-00:00
Session name: 18th European Congress of Clinical Microbiology and Infectious Diseases
Location: Barcelona, Spain
Presentation type:
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