Protein F, a fibronectin-binding protein of Streptococcus pyogenes, also binds human fibrinogen: isolation of the protein and mapping of the binding region.

During screening of a gene library of Streptococcus pyogenes type M15 for fibrinogen-binding material, a protein of approximately 100 kDa, encoded outside the vir region, was found. DNA sequencing revealed this component to be identical to protein F, a fibronectin-binding protein. Isolation of the recombinant protein, termed F15, was performed by the use of fibrinogen affinity chromatography.