Detailed description of the active site region in MtPncA.

<p><b>A</b> Superimposition of the active site regions in MtPncA (in green) and PhPncA (in red). The Fe2⁺ ion is depicted by an orange sphere, and water molecules by red spheres. The two proteins are shown in ribbon representation, with the side chains of interest in stick representation. <b>B</b> Details of the MtPncA active site in ribbon and stick representation. Hydrogen bonds are represented as black broken lines. <b>C</b> Modeling of the putative acyl-enzyme intermediate formed between the drug (PZA) and the side chain of Cys138 in MtPncA.</p

Unfolding of MtPncA and various mutants monitored in the presence of SYPRO orange.

<p>The proteins were gradually heated and the unfolding process was monitored by detection of the charges of fluorescence of the dye reporter that binds preferentially to the unfolded proteins <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015785#pone.0015785-Pantoliano1" target="_blank">[18]</a>. The fluorescence intensities (Y axis) are measured according to the temperature (X axis, in °C).</p

Ribbon representation of the structure of the <i>M. tuberculosis</i> PncA protein.

<p>The secondary structures, the iron binding site (Asp49, His51, His57, His71) and the catalytic triad (Cys138, Asp8, Lys96) are annotated. The iron ion is represented by the orange sphere, the two water molecules by red spheres.</p