Fig. 5
Protein expression from pFCF1 and pFBH1. a Whole-cell lysates from iron-starved E. coli BW25113 transformants (equivalent wet cell weights) were analyzed by Western blotting. An anti-FLAG antibody was used to detect expression of FLAG-EntA (left blot, left lane) and FLAG-T25 (right blot). Untransformed cell lysate probed with anti-FLAG antibody (left blot, right lane (‘ctrl’)). b Western blot of iron-starved E. coli BW25113 lysates probed with anti-HA antibody. Left lane: E. coli BW25113 transformed with pFBH1-entB. Right lane: Untransformed cell lysate (‘ctrl’). c Iron responsiveness of the bidirectional promoter region. Upper panel: anti-FLAG antibody was used to detect expression of FLAG-EntE in lysates from cells grown in minimal M9 medium supplemented with 2,2'-dipyridyl (left) and from cells grown in LB medium supplemented with FeSO4 (right). Lower panel: anti-GAPDH antibody was used to detect expression of E. coli GAPDH from protein samples identical to those in the upper panel