Fig 6. Validation of the in vivo Tn-seq screen.

Insertional mutants in selected genes identified by Tn-seq as associated with decreased (A) or increased (B) fitness in vivo in lesions were mixed with GAS 5448 (ca. 1:1 ratio) and monitored during competitive infection during soft tissue infection of CD1 outbred mice. Total CFU were determined from homogenized lesions harvested at 48 HPI and ratios expressed as competitive indexes (mut/wt). Results correlating with the in vitro Tn-seq screen for decreased (orange circles) and increased (green circles) fitness are shown. Results not validating Tn-seq data are displayed as grey circles. Unpaired student’s t-test was used to evaluate the significance of differences between groups; a p value of <0.05 (*) or <0.01 (**) was considered statistically significant.