In vitro and in vivo activity of new strains of Bacillus subtilis against ESBL-producing Escherichia coli: an experimental study.

Despite strong in vitro activities of new B. subtilis strains against ESBL-E. coli, intestinal colonisation was not altered by curative Bacillus treatment even if their spores proved to germinate in the gut. Thus, this work underlines the importance of in vivo experiments to identify efficient probiotics. The use of potential antimicrobial compounds identified by genome sequencing remains an attractive alternative to explore.