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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - A mechanism-inspired UDP-N-acetylglucosamine pyrophosphorylase inhibitor
AU - Raimi, Olwale G.
AU - Hurtado-Guerrero, Ramon
AU - Borodkin, Vladimir
AU - Ferenbach, Andrew
AU - Urbaniak, Mick
AU - Ferguson, Michael A J
AU - van Aalten, Daan M. F.
PY - 2020/3/24
Y1 - 2020/3/24
N2 - 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. Astructure with UDP-GlcNAc, pyrophosphate and Mg2+ provides the first Michaelis complex trapped for this class of enzyme, revealing the structural basis of the previously reported Mg2+ dependence and direct observation ofpyrophosphorolysis. 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 α,β-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.
AB - 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. Astructure with UDP-GlcNAc, pyrophosphate and Mg2+ provides the first Michaelis complex trapped for this class of enzyme, revealing the structural basis of the previously reported Mg2+ dependence and direct observation ofpyrophosphorolysis. 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 α,β-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.
U2 - 10.1039/C9CB0017H
DO - 10.1039/C9CB0017H
M3 - Journal article
VL - 2020
SP - 13
EP - 25
JO - RSC Chemical Biology
JF - RSC Chemical Biology
IS - 1
ER -