1. Academic Validation
  2. Structural and Mechanistic Insights into Atypical Bacterial Topoisomerase Inhibitors

Structural and Mechanistic Insights into Atypical Bacterial Topoisomerase Inhibitors

  • ACS Med Chem Lett. 2025 Apr 1;16(4):660-667. doi: 10.1021/acsmedchemlett.5c00060.
Paul D Toth 1 Steven C Ratigan 1 Joshua W Powell 1 Sydney R Cassel 1 Jack C Yalowich 1 Craig A McElroy 1 Steffen Lindert 1 Charles E Bell 1 Mark J Mitton-Fry 1
Affiliations

Affiliation

  • 1 Department of Chemistry and Biochemistry, College of Arts and Sciences, Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Division of Pharmaceutics and Pharmacology, College of Pharmacy, Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States of America.
Abstract

Novel bacterial Topoisomerase inhibitors (NBTIs) targeting DNA gyrase and Topoisomerase IV constitute a new Antibacterial class for deadly pathogens such as MRSA. While most NBTIs induce gyrase-mediated single-strand DNA breaks, a subset of amide NBTIs induces both single-strand and double-strand DNA breaks. Here, we report the X-ray crystal structures of two such amide NBTIs, 148 and 185, and demonstrate an unusual binding mode characterized by engagement of both GyrA D83 and R122. The synthesis of two isosteric triazole NBTIs is also described, one of which (342) affords only single-strand DNA breaks, while the Other (276) also induces both single- and double-strand DNA breaks. A combination of docking and molecular dynamics simulations is employed to further investigate the potential structural underpinnings of differences in DNA cleavage.

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