BFP expression is reduced in EPEC mutants lacking dsbA, degP and cpxP. A. Western analysis of bundlin (BfpA), BfpB, BfpC and BfpD expression in wild-type and mutant EPEC strains: lane 1, wild-type (E2348/69); lane 2, bfp- strain (JPN15); lane 3, degP::kan (ALN188); lane 4, ppiA::kan (ALN190); lane 5, cpxP::kan (ALN194); lane 6, dsbA::kan (TR1121). Whole-cell lysates were collected from EPEC grown in DMEM/F12 as described in Experimental procedures. Samples were collected from each strain at least three times; one representative blot is shown. Arrows denote non-specific bands (NSB). B. Results of autoaggregation assay performed on EPEC Cpx regulon mutants. Autoaggregation assays were performed as described in Experimental procedures; the overall average and standard deviation resulting from two separate experiments performed in triplicate are shown. One asterisk (*) denotes a value significantly different from positive control E2348/69; two asterisks (**) denote a value significantly different from both E2348/69 and negative control JPN15 (one-way anova with Bonferroni's multiple comparison test; P < 0.05).