Quinacrine modifies the <i>F. tularensis</i> MglA and SspA interaction in a bacterial two-hybrid system.

<p>Transcription activation by the interaction between MglA and SspA from <i>F. tularensis</i> SCHU S4 decreases in the presence of quinacrine. The plasmid constructs pBR-<i>mglA</i>-ω and pACTR-<i>sspA</i>-Zif were transformed in the <i>E. coli</i> reporter strain AW23 (Δ<i>sspA</i>). Cells were grown in presence (open square) or absence (closed squares) of 100 µM quinacrine, and assayed for β-galactosidase activity (expressed in arbitrary units, AU). For ease of presentation the base level expression activity obtained with the empty plasmids (pACTR-AP-Zif and pBR-GP-ω; <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054498#pone.0054498.s001" target="_blank">Fig. S1</a>) was subtracted from those with pBR-<i>mglA</i>-ω and pACTR-<i>sspA</i>-Zif.