Figure 2.

Structure of S. aureus PK in complex with compound 6. A, tetrameric structure of PK illustrating the ligand density at the small interface. Position of active and effector sites are for reference only. B, interface binding pocket. Refined ligand position shown with ligand omit map (green). Anomalous map calculated from data collected at bromine edge (purple) indicates the position of the ligand bromine atoms. Residues lining the binding pocket from chain A are labeled. Hydrogen bonds between Ser362 and indole nitrogens are marked in red. C and D, comparison of S. aureus (C) and representative human PK structure (PDB 1ZJH) (D) illustrating closer packing of helix 340–350 and differences in the primary structure of this helix and the interface binding pocket, which contribute to selectivity. This research was originally published in the Journal of Biological Chemistry. R. Zoraghi et al. Methicillin-resistant Staphylococcus aureus (MRSA) Pyruvate Kinase as a Target for Bis-indole Alkaloids with Antibacterial Activities. J. Biol. Chem. 2011; 286, 44716–44725. © the American Society for Biochemistry and Molecular Biology.