This entry represents the C-terminal domain of MurT ligase from Gram-positive bacteria. MurT is part of the bi-enzymatic complex MurT-GatD involved in the amidation of the alpha-carboxyl group of the D-isoglutamate residue in Lipid II in the peptidoglycan layer to produce D-isoglutamine. This domain contains an aspartate at position 349, the third residue in the catalytic triad GatD-C94, GatD-H189, MurT-D349. This C-terminal domain is built around a central six-stranded, predominantly parallel beta-sheet that is sandwiched between four alpha-helices on one side and two alpha-helices on the other. The MurT-GatD heterodimer adopts a boomerang-shaped conformation, with GatD packing against the C-terminal domain of MurT [1].

1: Structural basis of cell wall peptidoglycan amidation by the GatD/MurT complex of Staphylococcus aureus. Noldeke ER, Muckenfuss LM, Niemann V, Muller A, Stork E, Zocher G, Schneider T, Stehle T; Sci Rep. 2018;8:12953. PMID:30154570