FIG. 3.

Comparison of the colonizing abilities of various E. coli strains by bioluminescence. Sets of four mice were fed with 10⁷ CFU of MG1655-Str^r/pAL2(pVA838ΩP_amiluxABCDE) (A), MG1655-Str^r/pAT881(pGB2ΩP_amiluxABCDE) (B), 55989-Str^r/pAL2(pVA838ΩP_amiluxABCDE) (C), or BM2711-Str^r/pAL2(pVA838ΩP_amiluxABCDE) (D). At the indicated times, colonization was monitored by enumeration of bacteria in the feces plated on streptomycin (100 μg/ml), erythromycin (Em) (150 μg/ml), or spectinomycin (Sp) (50 μg/ml) and by measuring the bioluminescent signal in feces or (E) transcutaneously in whole animals. At every time point, log₁₀ means of the CFU per gram of feces, photons/s per gram of feces, and photons/s in whole animals for each set of four mice in a given experiment are plotted, with standard errors shown.