Journal article
Fluoroquinolone interactions with Mycobacterium tuberculosis gyrase: Enhancing drug activity against wild-type and resistant gyrase
Proceedings of the National Academy of Sciences - PNAS, Vol.113(7), pp.E839-E846
02/16/2016
DOI: 10.1073/pnas.1525055113
PMCID: PMC4763725
PMID: 26792518
Abstract
Mycobacterium tuberculosis is a significant source of global morbidity and mortality. Moxifloxacin and other fluoroquinolones are important therapeutic agents for the treatment of tuberculosis, particularly multidrug-resistant infections. To guide the development of new quinolone-based agents, it is critical to understand the basis of drug action against M. tuberculosis gyrase and how mutations in the enzyme cause resistance. Therefore, we characterized interactions of fluoroquinolones and related drugs with WT gyrase and enzymes carrying mutations at GyrA(A90) and GyrA(D94). M. tuberculosis gyrase lacks a conserved serine that anchors a water-metal ion bridge that is critical for quinolone interactions with other bacterial type II topoisomerases. Despite the fact that the serine is replaced by an alanine (i.e., GyrA(A90)) in M. tuberculosis gyrase, the bridge still forms and plays a functional role in mediating quinolone-gyrase interactions. Clinically relevant mutations at GyrA(A90) and GyrA(D94) cause quinolone resistance by disrupting the bridge-enzyme interaction, thereby decreasing drug affinity. Fluoroquinolone activity against WT and resistant enzymes is enhanced by the introduction of specific groups at the C7 and C8 positions. By dissecting fluoroquinolone-enzyme interactions, we determined that an 8-methyl-moxifloxacin derivative induces high levels of stable cleavage complexes with WT gyrase and two common resistant enzymes, GyrA(A90V) and GyrA(D94G). 8-Methyl-moxifloxacin was more potent than moxifloxacin against WT M. tuberculosis gyrase and displayed higher activity against the mutant enzymes than moxifloxacin did against WT gyrase. This chemical biology approach to defining drug-enzyme interactions has the potential to identify novel drugs with improved activity against tuberculosis.
Details
- Title: Subtitle
- Fluoroquinolone interactions with Mycobacterium tuberculosis gyrase: Enhancing drug activity against wild-type and resistant gyrase
- Creators
- Katie J Aldred - Vanderbilt UniversityTim R Blower - Johns Hopkins MedicineRobert J Kerns - University of IowaJames M Berger - Johns Hopkins MedicineNeil Osheroff - Vanderbilt University
- Resource Type
- Journal article
- Publication Details
- Proceedings of the National Academy of Sciences - PNAS, Vol.113(7), pp.E839-E846
- DOI
- 10.1073/pnas.1525055113
- PMID
- 26792518
- PMCID
- PMC4763725
- NLM abbreviation
- Proc Natl Acad Sci U S A
- ISSN
- 0027-8424
- eISSN
- 1091-6490
- Grant note
- T32 CA09582 / NCI NIH HHS T32 CA009582 / NCI NIH HHS R01 CA077373 / NCI NIH HHS R01 AI087671 / NIAID NIH HHS R01 GM033944 / NIGMS NIH HHS R01 AI87671 / NIAID NIH HHS
- Language
- English
- Date published
- 02/16/2016
- Academic Unit
- Pharmaceutical Sciences and Experimental Therapeutics; Medicinal and Natural Products Chemistry
- Record Identifier
- 9984366030902771
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