Figure 1.

Predicted model of the 6c coordination state of the Human HNOX domain where the binding pocket heme is ligated to NO (6c NO-HNOX). The Y135-S137-R139 (Y-S-R) motif that bears strong interactions with the heme propionic moiety is also labeled (yellow). Functionally critical regions are also labeled as helix-f (red), loop α, β, and γ (yellow). A simple chemical scheme of heme is shown in the right panel. A detailed scheme of the heme interactions for each system are shown in Figure 7.