FIGURE 2.

Identification of the gp340-binding protein Spy0843. A, trypsin-treated cell surface extract of S. pyogenes NZ131Δrgg was applied on SDS-polyacrylamide gel. B, extract was transferred to nitrocellulose membrane and probed with biotinylated gp340. C, peptide data from one of the strongly stained bands identified it as Spy0843. D, binding of trypsin-extracted cell surface Spy0843 with native gp340 in human saliva in the absence or presence of soluble recombinant Spy0843 protein (r0843) and with non-biotinylated gp340. All bindings were detected with monoclonal anti-gp340 antibody.