FIG. 1.
Spatial organization of known Bordetella alcaligin siderophore system genes. The 20-kb XhoI insert DNA fragment of B. pertussis cosmid pCP1.11 is depicted at the top. The enlarged map in the center represents an approximately 12-kb BamHI-PstI subregion of pCP1.11; arrows indicate the direction of transcription and genetic limits of all known genes within the Bordetella alcaligin gene cluster, and open circles represent known or hypothetical Fur-regulated promoter-operator regions. The detailed lowermost map is enlarged to represent the 3.8-kb PstI DNA subregion encoding fauA, and a 1-kb scale bar is shown. FBS indicates the position of the computer-predicted Fur-binding site immediately upstream from the start of the fauA coding sequences. The approximate position of sequences complementary to mutagenic primer fau1 used in the construction of ΔfauA mutant BRM18 is indicated by the small arrow. The triangle indicates the position of the BglII site of insertion of the kanamycin resistance cassette (Kanr) in fauA mutant BRM17. Abbreviations: X, XhoI; B, BamHI; E, EcoRI; Sp, SphI; P, PstI; Sm, SmaI; K, KpnI; RV, EcoRV; Bg, BglII.