Fig 6.

Formation of BxpB trimers and BxpB trimer-BclA NTD peptide complexes in vivo. A heat-treated reaction mixture containing BxpB plus a peptide containing BclA residues 20–38 (+P) and exosporium proteins extracted from an equal number of spores of the CLT406, CLT306 (ΔbclA), and wild-type Sterne (Strn) strains of B. anthracis were analyzed by SDS-PAGE and western blotting with an anti-BxpB mAb (see text for additional details). Both the Coomassie-stained gel and a western blot are shown. The molecular masses of protein standards are indicated. The positions of BxpB monomers (M), dimers (D), and putative trimers (T) and of the apparent heat-stable BxpB-BclA NTD peptide complexes (C) are also marked.