Effect of vancomycin on the production of extracellular vesicles in Staphylococcus aureus

Extracellular vesicles (EVs) are nano-sized biological particles (30 to 150 nm) produced by any living cell that are actively secreted into the surrounding environment. They carry biologically active components involved in intercellular signaling and communication, and contribute to important physiological processes. Depending on their composition, they participate, among other things, in pathogenesis, modulation of the immune response and exchange of material. Secretory factors are important components of pathogenesis in Staphylococcus aureus, a major pathogen for human and animal health. The role of EVs in infections caused by S. aureus is poorly understood yet although. The human strain S. aureus HG003 derived from NCTC8325, widely used as a model in antibiotic resistance studies, has a regulatory sRNA involved in virulence and adaptation to antibiotics. However, the role of S. aureus HG003 EVs in antibiotic resistance has not been investigated yet. In this work, we characterized HG003 EVs, in terms of their protein and RNA content. The RNA-seq approach was used to characterize the RNA content of EVs from S. aureus HG003 prepared from early and late stationary growth phases in the presence and absence of vancomycin, an antibiotic frequently used in S. aureus treatment. Preliminary results showed that there is a significant increase in EVs diameter from late stationary growth phase of HG003 compared to early stationary phase, whereas no significant difference was observed in absence and presence of vancomycin. The transcriptome and proteome analyses of HG003 EVs and eukaryotic RNA-seq are ongoing. This work will improve our knowledge on the role of EVs in S. aureus pathogenesis, and in its adaptation of antibiotic treatment.