Fig. 5

Conserved amino acid residues in groups of potential HisN, Cg0911, SuhB, ImpA, and CysQ orthologs that can be used for the discrimination of the different protein groups. Numbering of the amino acids corresponds to the five proteins from C. glutamicum. The arrows indicate active site key residues that are involved in binding of the three catalytic metal ions, the phosphate group of the substrate and/or the activation of the water molecule for hydrolysis of the phosphate ester bond as derived from the solved crystal structures of various IMPases [28, 29]. Coloring: blue = Arg, Lys; red = Asp, Glu; pink = Ser, Thr; green = His, Phe, Trp, Tyr; black = all remaining