Effect of Bile Acid on the Cell Membrane Functionality of Lactic Acid Bacteria For Oral Administration.

MARÍA PÍA TARANTO; GASPAR PÉREZ MARTÍNEZ; FONT DE VALDEZ, G.

RESEARCH IN MICROBIOLOGY

Elsevier

Año: 2006 vol. 157 p. 720 - 725

0923-2508

Lactic acid bacteria and other species dwelling in the gut need to be tolerant to bile salts. This study was devoted to determine the effects of the bile salts taurodeoxycholate (TDCA) and deoxycholate (DCA) on Lactobacillus reuteri CRL 1098, a strain of likely probiotic value. When compared to other lactobacilli, Lactobacillus reuteri showed the highest survival rate, but was still sensitive to high (>3 mM) DCA concentrations. DCA produced the complete permeabilization of cells, abolished glucose uptake and severely distorted the cell envelope, as shown by electron microscopy. Detailed analytical studies revealed a change in phospholipids vs. glycolipids ratio and also in lipid proportions, C18:1 W9C form remarkably increased, possibly following a fast adaptive response during DCA treatment. This study provided the first solid evidences of the mechanism of DCA toxicity in a lactic acid bacterium.