Figure 3 Similarities and differences between NE1406 and the calycin superfamily. (a) Stereo ribbon diagram of the binding sites for the two buffer molecules 2-(N-cyclohexylamino)ethanesulfonic acid (CHES) and glycerol (GOL). Conserved residues
are indicated. (b) NE1406 exhibits the calycin-superfamily structural signature. Stereo ribbon diagram
of the N-terminal domain of NE1406 showing the stacked arginine and tryptophan residues
characteristic of the calycin fold (Flower et al., 2000 ). Hydrogen bonds are indicated by dashed lines. A glycerol molecule (cyan) mediates
bonding of Trp50 to the 310-helix. (c) Ribbon diagrams depicting the front and back view of NE1406 (PDB code 2ich , residues 24–220; gray) superposed with nitrophorin 4 from Rhodnius prolixus (PDB code 1d2u , residues 22–205; red. The heme ligand for nitrophorin 4 is colored cyan. (d) Ribbon diagrams depicting the front and back view of NE1406 (PDB code 2ich , residues 24–220; grey) superposed with avidin from Gallus gallus (PDB code 1avd , residues 3–125; pink). The Trp-Arg signatures are represented as sticks. The biotin
ligand for avidin is shown in cyan. |