Genotypic and phenotypic characterization of Lactobacillus strains with antipathogenic activities

Lactobacillus crispatus BC5 and Lactobacillus gasseri BC12 possess antipathogenic activities that makes them good candidates as probiotics. Indeed, it has been demonstrated that these Lactobacilli can carry out a fungistatic and fungicidal activities against Candida albicans, inhibit the Chlamydia trachomatis infectivity, reduce the Neisseria gonorrhoeae viability and inhibit HIV-1 replication. The aim of this study is to characterize L. crispatus and L. gasseri from genotypic and phenotypic point of views. Whole genome sequencing was performed followed by gene annotation, genome comparison and single gene analysis, with a specific focus on genes involved in antibiotic resistance and production of antimicrobial compounds. Phenotypic characterization was performed using Phenotype Microarray, revealing carbon and nitrogen sources used by these two strains as well as their specific sensitivity to several drugs and chemical compounds. Functional assays demonstrated the capacity of Lactobacillus biosurfactants to eradicate and inhibit the biofilm formation of methicillin resistant S. aureus (MRSA). Taken together, these results demonstrate that L. crispatus and L. gasseri having possible biotechnological applications, in particular, for the treatment and/or prevention of pathogen infections.