Figure 4.
Structure of: (a) Mb with bound oxygen (green, PDB: 1MBO) and after exposure of H2S (blue, PDB: 1YMC), and (b) SulfMb isoforms. The final sulfheme product is a modified chlorin-type heme with a sulfur atom incorporated into one of the pyrrole rings. Several isoform were identified in which sulfMbA is an episulfide, while sulfMbB and sulfMbC are characterized by a ring opened episulfide and a thiochlorin, respectively.
