6tn3

Publication Abstract from PubMed

UDP-N-acetylglucosamine pyrophosphorylase (UAP1) catalyses the last step in eukaryotic biosynthesis of uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc), converting UTP and GlcNAc-1P to the sugar nucleotide. Gene disruption studies have shown that this gene is essential in eukaryotes and a possible antifungal target, yet no inhibitors of fungal UAP1 have so far been reported. Here we describe the crystal structures of substrate/product complexes of UAP1 from Aspergillus fumigatus that together provide snapshots of catalysis. A structure with UDP-GlcNAc, pyrophosphate and Mg(2+) provides the first Michaelis complex trapped for this class of enzyme, revealing the structural basis of the previously reported Mg(2+) dependence and direct observation of pyrophosphorolysis. We also show that a highly conserved lysine mimics the role of a second metal observed in structures of bacterial orthologues. A mechanism-inspired UTP alpha,beta-methylenebisphosphonate analogue (meUTP) was designed and synthesized and was shown to be a micromolar inhibitor of the enzyme. The mechanistic insights and inhibitor described here will facilitate future studies towards the discovery of small molecule inhibitors of this currently unexploited potential antifungal drug target.

A mechanism-inspired UDP-N-acetylglucosamine pyrophosphorylase inhibitor.,Raimi OG, Hurtado-Guerrero R, Borodkin V, Ferenbach A, Urbaniak MD, Ferguson MAJ, van Aalten DMF RSC Chem Biol. 2020 Mar 24;1(1):13-25. doi: 10.1039/c9cb00017h. eCollection 2020 , Apr 16. PMID:34458745^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.