Spread of antimicrobial resistances urges a need for new drugs against Mycobacterium tuberculosis (Mtb) with mechanisms differing from current antibiotics. Previously, callyaerins were identified as promising anti-tubercular agents, representing a class of hydrophobic cyclopeptides with an unusual (Z)-2,3-di-aminoacrylamide unit. Here, we investigated the molecular mechanisms underlying their antimycobacterial properties. Structure-activity relationship studies enabled the identification of structural determinants relevant for antibacterial activity. Callyaerins are bacteriostatics selectively active against Mtb, including extensively drug-resistant strains, with minimal cytotoxicity against human cells and promising intracellular activity. By combining mutant screens and various chemical proteomics approaches, we showed that callyaerins target the non-essential, Mtb-specific membrane protein Rv2113, triggering a complex dysregulation of the proteome, characterized by global downregulation of lipid biosynthesis, cell division, DNA repair, and replication. Our study thus identifies Rv2113 as a previously undescribed Mtb-specific drug target and demonstrates that also non-essential proteins may represent efficacious targets for antimycobacterial drugs.

抗菌药物耐药性的蔓延迫切需要针对结核分枝杆菌(Mtb) 的新药物，其机制不同于现有抗生素。此前，callyaerins 被认为是有前途的抗结核药物，代表一类具有不寻常的 ( Z )-2,3-二氨基丙烯酰胺单元的疏水性环肽。在这里，我们研究了其抗分枝杆菌特性的分子机制。结构-活性关系研究能够鉴定与抗菌活性相关的结构决定因素。 Callyaerins 是选择性抑菌剂，可针对 Mtb（包括广泛耐药菌株）发挥作用，对人体细胞的细胞毒性极小，且具有良好的细胞内活性。通过结合突变体筛选和各种化学蛋白质组学方法，我们发现，callyaerins 靶向非必需的 Mtb 特异性膜蛋白 Rv2113，引发蛋白质组的复杂失调，其特征是脂质生物合成、细胞分裂、DNA 修复和代谢的整体下调。复制。因此，我们的研究将 Rv2113 确定为先前未描述的 Mtb 特异性药物靶点，并证明非必需蛋白也可能代表抗分枝杆菌药物的有效靶点。