Mycobacterium tuberculosis is one of the global leading causes of death due to a single infectious agent. Pretomanid and delamanid are new antitubercular agents that have progressed through the drug discovery pipeline. These compounds are bicyclic nitroimidazoles that act as pro-drugs, requiring activation by a mycobacterial enzyme; however, the precise mechanisms of action of the active metabolite(s) are unclear. Here, we identify a molecular target of activated pretomanid and delamanid: the DprE2 subunit of decaprenylphosphoribose-2’-epimerase, an enzyme required for the synthesis of cell wall arabinogalactan. We also provide evidence for an NAD-adduct as the active metabolite of pretomanid. Our results highlight DprE2 as a potential antimycobacterial target and provide a foundation for future exploration into the active metabolites and clinical development of pretomanid and delamanid.

结核分枝杆菌是单一传染源导致的全球主要原因之一。Pretomanid 和 delamanid 是新的抗结核药物，已通过药物发现流程取得进展。这些化合物是双环硝基咪唑，充当前药，需要通过分枝杆菌酶激活；然而，活性代谢物的确切作用机制尚不清楚。在这里，我们确定了激活的 pretomanid 和 delamanid 的分子靶点：十异戊二烯基磷酸核糖-2'-差向异构酶的 DprE2 亚基，这是一种合成细胞壁阿拉伯半乳聚糖所需的酶。我们还提供了 NAD 加合物作为 pretomanid 活性代谢物的证据。