The overexpression of LsrR decreased <i>Salmonella</i> invasion into HEp-2 epithelial cells, even when the requirement for motility is bypassed through centrifugation.

<p>Monolayers of HEp-2 epithelial cells were infected with the wild-type (WT) <i>Salmonella</i>, WT harboring backbone plasmid, pUHE21-2<i>lacI^q</i>, and WT harboring pJH1 strains in the presence or absence of 100 µM IPTG. To exclude the requirement of motility, mild centrifugation was employed (centri.). The numbers of internalized bacteria were determined as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037059#s4" target="_blank">Methods</a>. Values represent the relative amount of internalized bacteria and have been normalized to the level of internalization of WT strain, which was set at 1.00. Values are the average and standard deviation from three independent experiments, each done in triplicate.