FIG 2.
Bacteriophage transduction of the gneZ::spc allele. (A) The donor strain B. anthracis YW6(pJK4) was cultured in PA medium with 1 mM IPTG and lysed with bacteriophage CP-51. The lysate was used to cross the gneZ::spc allele into the recipient strain Sterne carrying either a vector control or the isogenic plasmid expressing gneZ from the constitutive hprK promoter (pgneZ). (B) Candidate transductants were selected on plates containing spectinomycin. (C) Spectinomycin-resistant colonies (Spcr clones) were enumerated after incubation of plates at 30°C for 24 h. Insertion of the correct spc allele was verified by DNA sequencing. Data from three independent experiments are shown with the total number of bacteria plated before spectinomycin selection.