Dissociated responses of vesiculogenesis and amoxicillin impact on extracellular vesicle production of first gut bacterial colonizers Bifidobacterium longum and Lactiplantibacillus plantarum

Bacterial extracellular vesicles (bEVs) have emerged as important mediators of microbiota–host interplay through the transport of active biomolecules, namely cargos, far from their release location. The neonatal period represents a critical window for the establishment of the gut microbiota and subsequent sustainable symbiotic communication. The gut primo-colonizing bacteria, including bifidobacteria and lactobacilli, likely contribute to the impact on the digestive, immune and neuron system maturation. However, exposures and experiences during this early stage may influence the development of health and diseases later on in life by altering these primo-interactions. As antibiotherapies are frequent in the postnatal period and associated to microbiota disorders, we evaluated the impact of amoxicillin on first colonizing Gram positive-derived EVs, using a robust and reproductible in-house workflow for the extraction and purification bEVs from Bifidobacterium longum and Lactiplantibacillus plantarum . The EVs production and the proteovesiculome profiles under amoxicillin treatment were compared. The results pointed out a dissociated response in the EVs release process and their regulation by amoxicillin according to strain with an enhance production of EVs for B. longum under amoxicillin. In addition, the proteovesicular analyses indicate that the vesicular protein profile was enriched and more diverse in B. longum -derived EVs from amoxicillin-treated cells than those from non-treated cells while the content shift in L. plantarum -derived EVs in amoxicillin-treated cells was in favor of protein richness loss. Overall, this study opens new avenues considering the impact of antibiotic therapies in the neonatal period on EVs derived from benefit Gram-positive gut bacteria.