Figure 7: Heme sensing by GBS during systemic infection.
(A) Heme sensing by GBS over the course of infection. Female BALB/c mice were infected with 2.107 CFU of WT(pPgbs0119-lux) or WT(pPØ-lux) strains. At 20 h post-infection, anesthetized mice were shaven and imaged organs in the IVIS 200 system (acquisition time, 20 min; binning 16; Methods). (B) Quantification of bioluminescence in live mice at 20 h post-infection. Luminescence of the abdomen of mice infected as in Fig. 5B was determined (Methods). Box and whiskers plot of data collected from 4 experiments (corresponding to a total of n = 25 mice per strain). The P value determined using a two-tailed Mann–Whitney test was 0.0002 (***P < 0.001). (C–F) Heme sensing versus bacterial establishment in dissected organs. Photograph, and overlap images of photograph and luminescence are shown BALB/c mice infected as in Fig. 2B were euthanized 20 h post-injection. All organs except the brain were imaged in a IVIS 200 system with acquisition times of 10 min and 5 min for WT(pPgbs0119-lux) and WT(plux) strains respectively; binning 16). No signal was detected in dissected organs of control mice inoculated with the control WT(pPØ-lux) strain. In visualization of brain (F), no signal was detected using WT(pPgbs0119-lux), while a strong signal was observed using the bacterial reporter WT(plux). we used acquisition time, 1 min, binning 16; as WT(pPgbs0119-lux) gave no luminescent signal in the brain (F), only the overlap photo is presented.
