The Staphylococcus aureus secretome

The bacterium Staphylococcus aureus is a dangerous pathogen that frequently causes problems in health care settings due to its high potential to develop resistance against antibiotics. The ability of S. aureus to cause disease is based on the production of a high number of proteins known as virulence factors, which allow the bacterium to survive and thrive in the human body. This takes place at the expense of an infected individual, who consequently develops the symptoms of disease. The virulence factors are synthesized inside the S. aureus cell with a specific signal that directs their transport across the cell envelope to the bacterial cell surface or the host tissues. During my PhD research, I have identified six different protein transport systems that can be used by S. aureus for the export of virulence factors. In addition, I have investigated which proteins contain specific transport signals pinpointing them as potential virulence factors. In total, about 160 proteins with transport signals were identified. This group of proteins includes a limited number of known virulence factors. Other studies were focused on the functional analysis of identified protein transport systems in S. aureus. Based on this research, a better understanding was obtained of the protein transport routes in S. aureus, and the proteins that follow these routes. The obtained results can possibly be used for the development of new approaches to detect and combat dangerous strains of S. aureus.