Fig. 1.

(a) Quantification of bacterial strains at different time points of an in vitro invasion assay in 5637 human bladder epithelial cells. ‘Total’ values represent intracellular bacteria, adherent bacteria and non-adherent bacteria in the cell supernatant isolated at 2 h post-infection (hpi). ‘Bound+Intracellular’ values represent adherent and intracellular bacteria isolated at 2 hpi. ‘Intracellular’ values represent intracellular bacteria isolated at 4 hpi following treatment with 200 ug ml⁻¹ gentamicin to eliminate extracellular bacteria. PAO1 and PA14 are lab strains of P. aeruginosa . UTI89 is a commonly studied strain of E. coli isolated from a urinary tract infection shown in yellow. All other strains are clinical UTI isolates of P. aeruginosa (n=3 for all strains). (b) Invasion rates of bacterial strains at different time points of an in vitro invasion assay in 5637 human bladder epithelial cells. Invasion rate is calculated by dividing the number of intracellular bacteria isolated at 4 h post-infection by the number of adherent and intracellular bacteria isolated at 2 h post-infection. Light green bar indicates strain contains exoS gene, Dark green bar indicates strain contains exoU gene. * Indicates an isolate’s mean rate of invasion is significantly different from PAO1’s (Tukey post-hoc test P<0.05). (n=3 for all strains).