Figure 4. Colony-forming units (CFU/mL) of the human sepsis-associated Escherichia coli (SEPEC) strains chosen for transmission electron microscopy and scanning electron microscopy that were recovered from the intracellular environment. All 49 strains were recovered at higher concentrations (up to 2 × 107 CFU/mL) than the positive control (EIEC O124:H) in the presence or absence of D-mannose in the medium. The negative control, E. coli C600, did not invade Vero cells.
