2.1 | Bacterial strains
Wild-type (WT) EPEC O127:H6 strain E2348/69 [streptomycin-resistant] and EPEC null mutants (ΔescN , ΔespB , ΔespD ) were used to purify EspB, to evaluate mAb-EspB-B7 binding, and to assess T3SS and translocation activities (Gauthier, Puente, & Finlay, 2003; Iguchi et al., 2009; Luo & Donnenberg, 2006). WT and T3SS-mutant strains ofCitrobacter rodentium DBS100 (Frankel et al., 1998), enterohemorrhagic E. coli (EHEC) (Deng et al., 2005), andSalmonella enterica serovar Typhimurium (Mills & Finlay, 1994) were used to assess antibody specificity. Antibiotics were used at the following concentrations: streptomycin (50 μg/mL), ampicillin (100 µg/mL), chloramphenicol (30 μg/mL), and nalidixic acid (50 μg/mL).