Structure of UDP-N-acetylglucosamine enolpyruvyl transferase, an enzyme essential for the synthesis of bacterial peptidoglycan, complexed with substrate UDP-N-acetylglucosamine and the drug fosfomycin

Abstract

The present structure reveals the mode of binding of the natural substrate UDP-GlcNAc and of the drug fosfomycin, and provides information on the residues involved in catalysis. These results should aid the design of inhibitors which would interfere with enzyme-catalyzed reactions in the early stage of the bacterial cell wall biosynthesis. Furthermore, the crystal structure of MurA provides a model for predicting active-site residues in EPSP synthase that may be involved in catalysis and substrate binding.

Clinical significance of the pharmacokinetic and pharmacodynamic characteristics of fosfomycin for the treatment of patients with systemic infections

“…Specifically, fosfomycin binds to and inhibits the cytoplasmic enzyme uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) enolpyruvyl transferase (MurA). This enzyme is responsible for the synthesis of UDP-Nacetylenolpyruvylglucosamine, which is a metabolic pentapeptide intermediate in the biosynthesis of the peptidoglycan layer of the bacterial cell wall [37]. To exert its action, fosfomycin needs to penetrate the bacterial cell membrane.…”

Determinants of Regioselectivity and Chemoselectivity in Fosfomycin Resistance Protein FosA from QM/MM Calculations

“…13 The metal is pentacoordinated in a trigonal-bipyramidal fashion, with the glutamate oxygen and the oxirane oxygen in the axial positions. EPR studies of FosA showed that the Mn 2+ ion (3d 5 ) is in the high-spin sextet state. 21,22 Interestingly, a K + ion was found in a loop close to the active site, consistent with the important role of K + for enzyme activity.…”

Functional Consequence of Covalent Reaction of Phosphoenolpyruvate with UDP-N-acetylglucosamine 1-Carboxyvinyltransferase (MurA)

“…However, the discovery that Cys-115 could be replaced by an aspartate without loss of activity (a mutation found in some bacteria including Mycobacteria) led to the conclusion that Cys-115 functions as a general acid-base catalyst and not as a nucleophile in the reaction with PEP (10). Cys-115 is a member of a 10-residue loop in the N-terminal globular domain that undergoes drastic conformational changes upon binding of UNAG by approaching the interdomain cleft and positioning the Cys-115 side chain into the PEP binding site (11)(12)(13)(14)(15). Cys-115 has received considerable attention as the target of covalent modification by fosfomycin (12) and other electrophilic natural products such as terreic acid (16) and cnicin (17).…”