Fibronectin-binding protein A (FnBPA) (FnBPA)

Fibronectin-binding protein A (FnBPA) is a prominent cell-wall-anchored surface protein of Staphylococcus aureus and a member of the microbial surface component recognizing adhesive matrix molecules (MSCRAMM) family (UniProt P14738). It plays a fundamental role in bacterial pathogenesis by mediating high-affinity binding to host extracellular matrix components, including fibronectin, fibrinogen, and elastin (PubMed: 11585510). This interaction not only facilitates initial colonization but also triggers the internalization of S. aureus into non-professional phagocytic cells, such as endothelial cells and osteoblasts, via a fibronectin bridge to host integrin alpha-5 beta-1 (PubMed: 10858309). FnBPA is significantly involved in the formation of biofilms and the development of invasive diseases such as infective endocarditis, septic arthritis, and osteomyelitis (PubMed: 22434304). As a critical virulence factor, it is a major focus for the development of novel therapeutic strategies, including monoclonal antibodies and multi-component vaccines aimed at blocking bacterial adhesion and invasion. Despite its potential, therapeutic development must account for the functional redundancy provided by its paralog, FnBPB.

Other names

fnbAFnBP-AFibronectin-binding protein A of Staphylococcus aureusStaphylococcus aureus surface protein FnBPA

Inhibition of bacterial adhesion to host extracellular matrix and prevention of host cell invasion by blocking fibronectin and fibrinogen binding sites, or by inducing opsonophagocytic killing through vaccine-induced antibodies.