FIG 2 .

Detection of BapA in envelope fractions of P. denitrificans. Planktonic phase cells were harvested from biofilm assays (grown in liquid L broth supplemented with 10 mM calcium chloride), and envelope fractions were prepared and separated by SDS-PAGE. The protein indicated by the arrow was shown by mass spectrometry to be BapA. The strains analyzed were as follows: lane 1, ΔbapBCD mutant; lane 2, wild type; lane 3, ΔhnoX mutant; lane 4, ΔdgcA mutant; lane 5, ΔdgcB mutant; lane 6, ΔdgcA ΔdgcB mutant; lane 7, Δhmp mutant; lane 8, Δhmp ΔhnoX mutant; lane 9, Δnor mutant. Two gel images are shown since the number of samples exceeded the capacity of the gel apparatus.