PMID: 25767118

Authors:

Renner-Schneck M, Hinderberger I, Gisin J, Exner T, Mayer C, Stehle T

Title:

Crystal structure of the N-acetylmuramic acid alpha-1-phosphate (MurNAc-alpha1P) uridylytransferase MurU, a minimal sugar-nucleotidyltransferase and potential drug target enzyme in Gram-negative pathogens.

Journal:

J Biol Chem. 2015 Mar 12. pii: jbc.M114.620989.

Abstract:

The N-acetylmuramic acid alpha-1-phosphate (MurNAc-alpha1P) uridylyltransferase MurU catalyzes the synthesis of uridine diphosphate (UDP)-MurNAc, a crucial precursor of the bacterial peptidoglycan cell wall. MurU is part of a recently identified cell wall recycling pathway in Gram-negative bacteria that bypasses the general de-novo biosynthesis of UDP-MurNAc and contributes to high intrinsic resistance to the antibiotic fosfomycin, which targets UDP-MurNAc de novo biosynthesis. To provide insights into substrate binding and specificity, we solved crystal structures of MurU of Pseudomonas putida in native and ligand-bound states at high resolution. With the help of these structures, critical enzyme- substrate interactions were identified that enable tight binding of MurNAc-alpha1P to the active site of MurU. The MurU structures define a "minimal domain" required for general nucleotidyltransferase activity. They furthermore provide a structural basis for the chemical design of inhibitors of MurU, which could serve as novel drugs in combination therapy against multi-resistant Gram-negative pathogens.