FIG. 3.
Growth of E. coli K-12 catecholate siderophore receptor-negative ΔtonB H5058 strain QT1272 (A) or QT1272 complemented with tonB (pIJ159) (B) containing a cloned copy of iha (pIJ84, ▴), fepA (pIJ68, ▵), or the control vector (pACYC184, ⋄) in minimal medium (M63 glucose) supplemented with 50 μM 2,2′-dipyridyl and 50 μM of enterobactin and its DHBS products.