Figure 1

Structure of the co-complex of the P. aeruginosa cNOR and the cd₁NiR dimer (PDB ID: 5GUW²⁴). (a) The full 2:2 structure with the two cNOR molecules in light green (NorC) and teal (NorB) and the cd₁NiR dimer in blue/gray. (b) Enlargement of the co-complex interaction area for cd₁NiR and a single cNOR, with the interaction between Arg-71 (cd₁NiR, blue stick) and Glu-119 (cNOR, green stick) shown. Also shown are schematic outlines of the cytoplasmic membrane in which cNOR sits and the path for NO from the release from the d₁ heme of cd₁NiR (pink) into the membrane from which it would travel through the suggested gas channel (indicated by green sticks) to the active site heme b₃ (pink) in cNOR²⁵. Also highlighted is the initial electron-accepting heme c in NorC (pink), other heme groups in grey.