Identification of surface proteins involved in the adhesion of a probiotic Bacillus cereus strain to mucin and fibronectin

Abstract

SeveralBacillusstrains isolated from commercial probiotic preparations were identified at the species level, and their adhesion capabilities to three different model intestinal surfaces (mucin, Matrigel and Caco-2 cells) were assessed. In general, adhesion of spores was higher than that of vegetative cells to the three matrices, and overall strainBacillus cereusCHdisplayed the best adhesion. Different biochemical treatments revealed that surface proteins ofB. cereusCHwere involved in the adhesion properties of the strain. Surface-associated proteins from vegetative cells and spores ofB. cereusCHwere extracted and identified, and some proteins such as S-layer components, flagellin and cell-bound proteases were found to bind to mucin or fibronectin. These facts suggest that those proteins might play important roles in the interaction of this probioticBacillusstrain within the human gastrointestinal tract.