In addition, some genes that are known to function in virulence, including omp25 (Edmonds et al., 2002), omp31 (Caro-Hernández et al., 2007), vjbR (Uzureau et al., 2007), htrA (Elzer et al., 1996), gntR (Haine et al., 2005), and dnaK (Köhler et al., 1996), were analyzed for their expression profiles in a hfq-deletion mutant during infection. This evidence concerns the gene HTRA1 and infection.