Figure 2.

HO system inhibitors. (A) The first generation of HO competitive inhibitors are based on the protoporphyrin structure shared by the heme group. (B) Azalanstat structure, basis of the second generation of non-competitive HO inhibitors. Central and eastern regions originate the imidazole-dioxolane compounds. (C) Small molecules that inhibit bacterial heme oxygenase (HemO), differences in the heme-binding pocket between the pathogen and host allow these approaches to act as bacteria-specific antimicrobial drugs.