The coenzyme A (CoA) biosynthesis pathway has attracted attention as a potential target for much-needed novel antimicrobial drugs, including for the treatment of tuberculosis (TB), the lethal disease caused by Mycobacterium tuberculosis (Mtb). Seeking to identify inhibitors of Mtb phosphopantetheine adenylyltransferase (MtbPPAT), the enzyme that catalyses the penultimate step in CoA biosynthesis, we performed a fragment screen. In doing so, we discovered three series of fragments that occupy distinct regions of the MtbPPAT active site, presenting a unique opportunity for fragment linking. Here we show how, guided by X-ray crystal structures, we could link weakly-binding fragments to produce an active site binder with a K D <20 μM and on-target anti-Mtb activity, as demonstrated using CRISPR interference. This study represents a big step toward validating MtbPPAT as a potential drug target and designing a MtbPPAT-targeting anti-TB drug.
A fragment screen yielded three series of Mycobacterium tuberculosis phosphopantetheinyl adenylyltransferase (MtbPPAT) ligands that bind to distinct regions within the active site. This presented a unique opportunity for fragment linking that was exploited for the design of higher affinity ligands, shown, using CRISPR interference, to possess on‐target antimycobacterial activity.
Keywords: Coenzyme A; Drug Discovery; Enzymes; Fragment-Based; Tuberculosis.
© 2023 The Authors. Angewandte Chemie published by Wiley-VCH GmbH.