Figure 3.

Structural comparison. (A) Superimposition of yPDE1 (cyan ribbons) over a metallo-β-lactamase-like protein from Gram-negative B. melitensis (green). Two zinc ions of yPDE1 are shown as red spheres, while two manganese ions of the bacterium are drawn as blue spheres. GMP (pink) is from yPDE1, and GMP in the bacterial structure (yellow) shows an opposite orientation. (B) Detailed view of GMP binding. The metal binding residues are identical in the two proteins. The yPDE1 residues are labeled.