Figure 1
(a) Electron density (e.d.) of chain C active site flexible loop (8–31). E.d. (2Fo-Fc map) is shown in green at 0.273 e/Å3—7 r.m.s.d., residues as ball and stick. The fragment starting and ending residues are labeled, as well as residues G16 and G17, which showed poor e.d. and were modeled with 0 occupancy. (b, c) Superposition of the catalytic region of APO-EcAII protomer A (purple, PDB ID: 6IZY) and C (green) and EcAII-ASP (pink, PDB ID: 1NNS). The l-Asp ligand is represented as sticks. In (c) only regions different in the three structures are colored. (d) EcAII-ASP flexible loop anchoring points. Residues involved in hydrogen bonds are represented as sticks. (e) APO-EcAII (protomer C) flexible loop anchoring points. Residues involved in loop anchoring in the l-Asp-bound structure are represented as sticks for comparison. (f) Triangular network between intimate dimer residues relevant for catalysis in the EcAII-ASP structure.
