Protein-mediated Adhesion of Lactobacillus fermentum Strain 737 to Mouse Stomach Squamous Epithelium

Abstract

The mechanism of adhesion of Lactobacillus fermentum strain 737 to mouse stomach squamous epithelium was investigated. Adhesion inhibition tests involving chelators, monosaccharides, periodate and concanavalin A and the use of bacteria grown in the presence of tunicamycin failed to clarify the adhesive mechanism. Washed bacterial cells had reduced adhesive capacity, except in the presence of spent broth culture supernatant fraction or cell washings. Spent culture supernatant fractions of erythrosine-supplemented broth did not enhance adhesion of washed cells. The adhesion-promoting factor(s) in the spent broth culture supernatant fractions and cell washings bound to both bacterial and epithelial cell surfaces, but did not promote adhesion of two other Lactobacillus strains which were not of mouse origin, thereby indicating host specificity for the adhesion-promoting activity. Chemical characteristics of the adhesionpromoting factor were determined by pretreatment of the dialysis retentate of spent broth culture supernatant fractions with proteolytic enzymes, concanavalin A-Sepharose or periodate before the adhesion assay. The adhesin was non-dialysable, pronase-sensitive, heat sensitive at 100 "C, had no affinity for concanavalin A-Sepharose and contained no carbohydrate groups active in the adhesion process. The protein profiles of dialysis retentates of spent broth culture supernatant fractions after bacterial growth in the absence and presence of erythrosine were determined by 2-dimensional SDS-PAGE. Gel filtration by HPLC was used for purification of an adhesion-promoting fraction. The host-specific adhesion of L. fermenturn strain 737 was mediated by a protein, with an M , of 12-13000, that was not detectable in cells grown in the presence of erythrosine. A model for the mode of binding of the adhesin to host epithelia and bacterial surfaces is proposed.

Role of Internalization in the Pathogenicity of Shiga Toxin‐Producing Escherichia coli Infection in a Gnotobiotic Murine Model

“…LAB adhere to the epithelial cells of the gastrointestinal tract by secreting a proteinaceous component (5). Moreover, this attaching property of LAB has been reported to exert an inhibitory effect on the adhesion of many kinds of pathogenic enterobacteria to intestinal cells (3).…”

Adhesion of Probiotic Bacteria to Resistant Rice Starch

“…2). Extracellular components have been played an important role in the adhesion of Lactobacillus fermentum and L. acidophilus to human intestinal cells (Conway and Kjelleberg, 1989;Coconnier et al, 1992).…”

Effets des bact�ries lactiques ing�r�es avec des laits ferment�s sur la sant�

“…L'idée générale est qu'une forte adhésion des bactéries lactiques à l'épithélium intestinal interférerait avec celle des agents pathogènes par saturation des sites de fixation. L'adhésion des bacté-ries lactiques à l'épithélium digestif a été étudiée in vitro avec des lignées cellulaires d'origine colique ou intestinale (Caco-2 et HT-29 par exemple), animale [16,27,54,115] ou humaine [9,10,21]. Les bactéries lactiques capables d'adhérer in vitro à l'épi-thélium humain et animal sont principalement des lactobacilles et certaines bifidobactéries isolées de la microflore humaine [9,21,25].…”

“…Pour certaines bactéries, l'adhé-sion est calcium dépendante alors que pour d'autres, elle ne l'est pas [21]. Plusieurs études suggèrent que l'adhésion est médiée par des protéines [10,27,54] alors que d'autres suggèrent un rôle des acides lipoteichoiques [19,50] et des carbohydrates [10,16]. Pour certaines souches, deux facteurs semblent impliqués dans l'adhésion, un facteur lié à la paroi cellulaire et un facteur sécrété [25].…”