Adhesion to the digestive mucosa is not sufficient for durable persistence of different Lactobacillus fermentum strains in the digestive tract of mice

Abstract

Adhesion to the digestive mucosa has often been considered as necessary for persistence of lactobacili in the gut and associated benefits. The behaviour of Lactobacillus fermentum strains isolated from pigs was investigated in the digestive contents and gastric epithelium of monoassociated and gnotobiotic mice. LEMPL9, a colonising strain, was adherent in both conditions. LEM1.16A, a non-colonising strain, and LEM1.16ANTG, a colonising mutant of LEM1.16A, were both non-adherent in monoassociation conditions, indicating that adhesion to the gastric mucosa is not essential for durable establishment in the gastrointestinal tract. The presence of a microflora was shown to have a positive impact on the Lactobacillus adhesion ability.