Structure of Extracellular Vesicles and Their Effect on Bacterial Biofilms Change with the Development of Antibiotic Resistance in the Probiotic Strain Lactiplantibacillus plantarum 8p-a3.

Significant changes in lactobacillus-derived extracellular membrane vesicles, which transfer lipids, polysaccharides, proteins, and nucleic acids, were for the first time observed to accompany the development of resistance to antibiotics (amoxicillin and clarithromycin) in vitro in the probiotic strain Lactiplantibacillus plantarum 8p-a3. The changes occur together with large-scale genome rearrangements, changes in the profile of phenotypic sensitivity to antimicrobials of various groups, and evolution of virulence. Changes in vesicles affected their structure, composition, and activity against biofilms of opportunistic bacteria. The data provide for a better understanding of the molecular mechanisms of microbial survival under selective pressure of antimicrobials, the functional potential of probiotic vesicles, and probiotic safety assessments.