Arenicolide Family Macrolides Provide a New Therapeutic Lead Combating Multidrug-Resistant Tuberculosis

Abstract

The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis (Mtb) poses a significant threat to health globally. During searching for new chemical entities regulating MDR- and XDR-Mtb, chemical investigation of the black oil beetle gut bacterium Micromonospora sp. GR10 led to the discovery of eight new members of arenicolides along with the identification of arenicolide A (Ar−A, 1), which was a previously reported macrolide with incomplete configuration. Genomic analysis of the bacterial strain GR10 revealed their putative biosynthetic pathway. Quantum mechanics-based computation, chemical derivatizations, and bioinformatic analysis established the absolute stereochemistry of Ar−A and arenicolides D−K (Ar−D−K, 2–9) completely for the first time. Biological studies of 1–9 revealed their antimicrobial activity against MDR and XDR strains of Mtb. Ar−A had the most potent in vitro antimicrobial efficacy against MDR- and XDR-Mtb. Mechanistically, Ar−A induced ATP depletion and destabilized Mtb cell wall, thereby inhibiting growth. Notably, Ar−A exerted a significant antimicrobial effect against Mtb in macrophages, was effective in the treatment of Mtb infections, and showed a synergistic effect with amikacin (AMK) in a mouse model of MDR-Mtb lung infection. Collectively, our findings indicate Ar−A to be a promising drug lead for drug-resistant tuberculosis. © 2024 Wiley-VCH GmbH.