Insertional inactivation mutants were generated in 6 genes associated with decreased fitness in vivo (RS02090/lytR, RS02780 /yvqE, RS04065/dltA, RS06590/adcA), RS06895 and RS08410/mga) and tested individually against WT 5448 using an in vivo competitive infection assay in the murine skin and soft tissue model (see Material and methods). This evidence concerns the gene PDYN and infection.