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Figure 3
Overall structure of T. album proteinase K. Three proteinase K structures (PDB code 6j43 in blue; PDB code 5kxu in orange; PDB code 4b5l in green) are presented as ribbon diagrams. In panels (a), (b), (c) and (d), detailed structures are drawn with mFo–DFc electron density maps, which are contoured at 2.0 σ (in grey mashes). The disulfide (Cys178 and Cys249) is indicated as a red arrow in panel (a). In panel (b), the catalytic triad (Ser–His–Asp) is depicted at its active site. Two Ca2+ ions with interacting residues and water molecules are shown in panels (c) and (d). Ca2+ ions and water molecules are coloured in magenta and red, respectively. The structures were constructed using PyMOL (DeLano, 2002 ![]() |