Molecular analysis of the interaction between protein A of Staphylococcus aureus and von Willebrand factor

Abstract

Staphylococcus aureus continues to be a major cause of infection in normal as well as immunocompromised hosts, and the increasing prevalence of highly virulent community acquired methicillin-resistant strains is a public health concern. Protein A (Spa) is a surface associated protein of S. aureus best known for its ability to bind to the Fc region of IgG. This interaction is of importance in resistance of S. aureus to phagocytosis. Spa also binds strongly to the Fab region of the immunoglobulins bearing Vh3 heavy chains and more recently has been shown to bind von Willebrand factor (vWF) and tumour necrosis factor receptor-1 (TNFR1). Each Spa domain is organized into a three helix bundle and binding sites for Fc and VH3 Fab have been identified.