Figure 6.

Structure-based sequence alignments of p261_C with p180_C (A) and p125_C with p353_C (B). Blue- and green-shaded boxes depict the α-helices and β-strands, respectively. The gray-shaded boxes indicate the residues that are disordered in the crystal structures of p261_C and p180_C. The secondary structure elements are from the crystal structures of p261_C and p180_C (A) and from Phyre (57) predictions for p125_C and p353_C (B). The conserved residues are highlighted in red. Magenta-shaded boxes depict the zinc-coordinating cysteines. Yellow bars indicate the sequences comprising the zinc-binding modules Zn1 and Zn2. The red bar indicates the sequences implicated in iron–sulfur cluster binding.