Probing the adhesion potential of Bifidobacterium animalis subsp. lactis MCM-B-2007 via in vitro and in silico analyses

Bifidobacterium strains are widely recognized for their probiotic properties, and their ability to adhere to the intestinal epithelium is crucial for effective gut colonization and interaction with the host. This study offers a thorough examination of the adhesion capabilities of Bifidobacterium animalis subsp. lactis, integrating in silico analyses with in vitro adhesion assessments. Genome analysis of MCM-B-2007 identified several adhesion proteins that might act as potential mediators of crosstalk between microbes and their host. Molecular docking studies further assessed these adhesion proteins interaction with gut mucins. MCM-B-2007 displayed the highest affinity for binding to MUC4, with a predicted weighted score of -1539.5. These adhesion capabilities were subsequently validated through in vitro adhesion assays. MCM-B-2007 demonstrated a significant adhesion potential, with an adhesion efficiency of approximately 306 ± 20 bacterial cells per 100 HT-29 cells, classifying it as a strongly adhesive strain. Additionally, MCM-B-2007 demonstrated the strong competitive inhibition of adhesion of pathogenic Klebsiella pneumoniae and Salmonella Typhimurium, effectively safeguarding the host cells against infections. These findings support its use as a probiotic with the potential for future application in establishing healthy gut microbiota.