The active site region in SdeAgu115A.
A, surface representation of the overall structure of SdeAgu115A dimer, with one of the active site regions highlighted by the rectangular box. B, close-up of the highlighted area that is formed by domains B (green), C (yellow), and D (red) from protomer A and domain C+′ (orange) from protomer B. The side chains of the candidate residues tested for their role in catalysis and substrate binding are displayed as sticks and labeled.