ISSN:
1745-4565
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
The entry of Salmonella into the intestinal epithelial cells is essential for its pathogenesis. In the present stuay, late logarithmic growth (12 h) in Luria Bertani broth supplemented (25, 50, or 100 mM) with acetate, propionate, butyrate, or a mixture of the three short-chain fatty acids (SCFA), influenced the ability ofS. typhimurium to associate and invade cultured HEp-2 cells. The response to SCFA addition was dependent on the concentration and the pH of the medium. Cell-association was decreased 4 to 100-fold at pH 6 and 2 to 20-fold at pH 7. At pH 7, invasion was increased 2-fold when bacteria were cultured in the presence of all concentrations of acetate and 25 mM propionate or butyrate; however, a 1.5 to 163-fold decrease in invasion occurred at pH 6 for all SCFA. The SCFA concentration also affected cell-association and invasion of S. typhimurium, especially at pH 6. In general, for each of the SCFA at pH 6 a lower percentage of cell-association and invasion was observed as the SCFA concentration was increased while at pH 7 decreases did not consistently occur as SCFA concentration was increased. These differences among the SCFA along with the pH effects suggest that the concentration of SCFA and the pH of the intestinal lumen may influence the expression of the invasion phenotype of S. typhimurium.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-4565.2000.tb00284.x
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