Fig. 2

Detection of pilus 2b polymerization and bacterial surface expression of pilus proteins. a Western blot analysis of total proteins from wild-type COH1 (WT), knockout mutant strain (Δbp-2b) lacking pilus 2b backbone protein (BP-2b) and Δbp-2b strain complemented with a plasmid expressing BP-2b (Δbp-2b+). The membrane was probed with a mouse monoclonal antibody (mAb) raised against BP-2b (α-BP-2b). b Flow cytometry analysis on whole fixed bacteria corresponding to wild-type COH1, mutant COH1 strains lacking the backbone protein of pilus 1 (Δbp-1) or of pilus 2b (Δbp-2b) and to the complemented strain Δbp-2b+. Bacteria were probed with mAbs against the backbone and the major ancillary proteins of pilus 1 (α -BP-1 and AP1–1) and pilus 2b (α -BP-2b and AP1-2b) and labeled with R-Phycoerythrin conjugated goat anti-mouse secondary antibodies. Black histograms indicate staining of bacteria with secondary antibodies only. The data are representative of three independent experiments