Biochemical analysis of secreted and surface proteins of Gram-positive bacteria in view of their use as components of effective vaccines

Research Group: Giampiero Pietrocola, Giulia Nobile, Stefania Giussani, Pietro Speziale, Simonetta Rindi

Staphylococcus aureus and Streptococcus agalactiae are the main human bacterial pathogens – dealing with infections caused by them can be quite challenging, due to the emergence of multi-drug resistant strains. In addition, these pathogens are able to evade the host immune system through the expression of several virulence factors, including secreted and surface-expressed proteins. Thus, a biochemical characterization of these proteins could lead to a breakthrough in developing novel antibacterial therapies. Ph.D. students will have the opportunity to clone and purify selected bacterial surface or secreted proteins and characterize them biochemically, structurally, and functionally in order to understand disease mechanisms to improve infection treatment and prevention. The doctoral student will also have the opportunity to generate monoclonal antibodies against critical epitopes of these antigens and test their therapeutic potential in animal models of infection.

Recent Publications:

• Alfeo MJ, Pagotto A, Barbieri G, Foster TJ, Vanhoorelbeke K, De Filippis V, Speziale P, Pietrocola G. Staphylococcus aureus iron-regulated surface determinant B (IsdB) protein interacts with von Willebrand factor and promotes adherence to endothelial cells. Sci Rep. 2021; 11(1):22799. doi: 10.1038/s41598-021-02065-w.
• Pietrocola G, Pellegrini A, Alfeo MJ, Marchese L, Foster TJ, Speziale P. The iron-regulated surface determinant B (IsdB) protein from Staphylococcus aureus acts as a receptor for the host protein vitronectin. J Biol Chem. 2020; 295(29):10008-10022. doi: 10.1074/jbc.RA120.013510.
• Pietrocola G, Nobile G, Alfeo MJ, Foster TJ, Geoghegan JA, De Filippis V, Speziale P. Fibronectin-binding protein B (FnBPB) from Staphylococcus aureus protects against the antimicrobial activity of histones. J Biol Chem. 2019; 294(10):3588-3602. doi: 10.1074/jbc.RA118.005707.