Figure 5.

The Pv-M17Δ125-151 X-ray crystal structure adopts the conserved hexameric conformation.A, 2.6 Å X-ray crystal structure of Pv-M17Δ125-151 adopts a hexameric conformation, composed of a “dimer or trimers”. Front trimer is depicted in shades of blue and chains are labeled A, B, and C. Back trimer is depicted in shades of green and chains are labeled X, Y, and Z. B, Pv-M17Δ125-151 X-ray crystal structure active site. Metal-coordinating residues are shown as green sticks, colored by atom. Zn1 and Zn2 are depicted as spheres. Zn1 is coordinated by the carboxyl group of Asp395, Asp475 and Glu477 and the amine group of Asp475. Zn2 is coordinated by the carboxyl group of Asp415, Asp395, Lys390 and Glu477. The sulfate ion is within binding proximity to the two zinc ions. C, close up of N-terminal region where the flexible loop (residues 125–151) of chain X was excised (yellow). Residues flanking excised region 124 and 152 depicted in yellow. The loop is adjacent to the substrate access channel and postulated substrate regulation loop of chain A (red). PDB ID: 6WVV.