Examination of inducibility of the Psp response in a <i>pspA</i> deletion strain in the presence of additional recombinant PspA, PspA(1–144), or Hip-PspA(145–222).

<p>(A) LacZ activity assays of a <i>pspA</i> deletion reporter strain (MC3), constitutively producing either mature HiPIP, PspA, PspA(1–144), or Hip-PspA(145–222). Production of TatA-Strep was induced by 0.1% (v/v) rhamnose at the beginning of the cultivation. The strain containing the empty vector pBW22 was used as negative control. The graph on the right side shows a rescaled plot of the results next to it. (B) SDS-PAGE/Western blot analysis of crude extract, soluble and membrane fractions of TatA-<i>Strep</i> producing strains used in (A). Western blots were developed using His-tag (upper panels) or PspA (lower panels) specific antibodies, * indicates a cross-reaction of the PspA antibody). TatA-Strep was detected via Strep-Tactin-HRP conjugate. “○”, biotin carboxyl carrier protein, BCCP. (C) Coelution analysis of Hip-PspA(145–222) with TatA-<i>Strep</i> produced in the <i>pspA</i> deletion reporter strain as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0198564#pone.0198564.g006" target="_blank">Fig 6</a>.