TBAJ-876 Retains Bedaquiline’s Activity against Subunits c and ε of Mycobacterium tuberculosis F-ATP Synthase

Autor: Priya Ragunathan, Christopher B. Cooper, Thomas Dick, Joon Shin, Jickky Palmae Sarathy, Anna M. Upton, Gerhard Grüber
Přispěvatelé: School of Biological Sciences
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Protein Conformation
Protein subunit
Mutant
Antitubercular Agents
F-ATP Synthase
ε subunit
F-ATP synthase
03 medical and health sciences
chemistry.chemical_compound
Bacterial Proteins
medicine
Pharmacology (medical)
Binding site
bedaquiline
Diarylquinolines
Mode of action
Mechanisms of Action: Physiological Effects
030304 developmental biology
Pharmacology
chemistry.chemical_classification
ε Subunit
0303 health sciences
c subunit
ATP synthase
biology
030306 microbiology
Chemistry
TBAJ-876
Mycobacterium tuberculosis
diarylquinoline
Molecular biology
3. Good health
Protein Subunits
Proton-Translocating ATPases
Infectious Diseases
Enzyme
Biological sciences::Molecular biology [Science]
Mechanism of action
Biological sciences::Biochemistry [Science]
biology.protein
medicine.symptom
Bedaquiline
Zdroj: Antimicrobial Agents and Chemotherapy
ISSN: 1098-6596
0066-4804
Popis: The antituberculosis drug bedaquiline (BDQ) inhibits Mycobacterium tuberculosis F-ATP synthase by interfering with two subunits. Drug binding to the c subunit stalls the rotation of the c ring, while binding to the ε subunit blocks coupling of c ring rotation to ATP synthesis at the catalytic α3:β3 headpiece. BDQ is used for the treatment of drug-resistant tuberculosis.
The antituberculosis drug bedaquiline (BDQ) inhibits Mycobacterium tuberculosis F-ATP synthase by interfering with two subunits. Drug binding to the c subunit stalls the rotation of the c ring, while binding to the ε subunit blocks coupling of c ring rotation to ATP synthesis at the catalytic α3:β3 headpiece. BDQ is used for the treatment of drug-resistant tuberculosis. However, the drug is highly lipophilic, displays a long terminal half-life, and has a cardiotoxicity liability by causing QT interval prolongation. Recent medicinal chemistry campaigns have resulted in the discovery of 3,5-dialkoxypyridine analogues of BDQ that are less lipophilic, have higher clearance, and display lower cardiotoxic potential. TBAJ-876, which is a new developmental compound of this series, shows attractive antitubercular activity and efficacy in a murine tuberculosis model. Here, we asked whether TBAJ-876 and selected analogues of the compound retain BDQ’s mechanism of action. Biochemical assays showed that TBAJ-876 is a potent inhibitor of mycobacterial F-ATP synthase. Selection of spontaneous TBAJ-876-resistant mutants identified missense mutations at BDQ’s binding site on the c subunit, suggesting that TBAJ-876 retains BDQ’s targeting of the c ring. Susceptibility testing against a strain overexpressing the ε subunit and a strain harboring an engineered mutation in BDQ’s ε subunit binding site suggest that TBAJ-876 retains BDQ’s activity on the ε subunit. Nuclear magnetic resonance (NMR) titration studies confirmed that TBAJ-876 binds to the ε subunit at BDQ’s binding site. We show that TBAJ-876 retains BDQ’s antimycobacterial mode of action. The developmental compound inhibits the mycobacterial F-ATP synthase via a dual-subunit mechanism of interfering with the functions of both the enzyme’s c and ε subunits.
Databáze: OpenAIRE