title: The Carbonic Anhydrase Inhibitor Ethoxzolamide Inhibits the Mycobacterium tuberculosis PhoPR Regulon and Esx-1 Secretion and Attenuates Virulence.
abstract: Mycobacterium tuberculosis must sense and adapt to host environmental cues to establish and maintain an infection. The two-component regulatory system PhoPR plays a central role in sensing and responding to acidic pH within the macrophage and is required for M. tuberculosis intracellular replication and growth in vivo. Therefore, the isolation of compounds that inhibit PhoPR-dependent adaptation may identify new antivirulence therapies to treat tuberculosis. Here, we report that the carbonic anhydrase inhibitor ethoxzolamide inhibits the PhoPR regulon and reduces pathogen virulence. We show that treatment of M. tuberculosis with ethoxzolamide recapitulates phoPR mutant phenotypes, including downregulation of the core PhoPR regulon, altered accumulation of virulence-associated lipids, and inhibition of Esx-1 protein secretion. Quantitative single-cell imaging of a PhoPR-dependent fluorescent reporter strain demonstrates that ethoxzolamide inhibits PhoPR-regulated genes in infected macrophages and mouse lungs. Moreover, ethoxzolamide reduces M. tuberculosis growth in both macrophages and infected mice. Ethoxzolamide inhibits M. tuberculosis carbonic anhydrase activity, supporting a previously unrecognized link between carbonic anhydrase activity and PhoPR signaling. We propose that ethoxzolamide may be pursued as a new class of antivirulence therapy that functions by modulating expression of the PhoPR regulon and Esx-1-dependent virulence.
authors.affiliation: Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA.
authors.forename: Benjamin K
authors.initials: BK
authors.lastname: Johnson
authors.affiliation: Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Colvin
authors.affiliation: Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA.
authors.forename: David B
authors.initials: DB
authors.lastname: Needle
authors.affiliation: Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.
authors.forename: Felix
authors.initials: F
authors.lastname: Mba Medie
authors.affiliation: Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.
authors.forename: Patricia A DiGiuseppe
authors.initials: PA
authors.lastname: Champion
authors.affiliation: Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA abramov5@msu.edu.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Abramovitch
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002257:Carbonic Anhydrase Inhibitors / Q000494:pharmacology*; D002256:Carbonic Anhydrases / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D005016:Ethoxzolamide / Q000494:pharmacology*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects / Q000235:genetics; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation / Q000187:drug effects / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D018085:Regulon / Q000187:drug effects*; D014376:Tuberculosis / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D014774:Virulence / Q000187:drug effects* / Q000235:genetics
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D002257:Carbonic Anhydrase Inhibitors; C093276:ESAT-6 protein, Mycobacterium tuberculosis; D002256:Carbonic Anhydrases; D005016:Ethoxzolamide