Dual inhibition of the terminal oxidases eradicates antibiotic-tolerant Mycobacterium tuberculosis.

EMBO molecular medicine, Volume: 13, Issue: 1
January 11, 2021
Bei Shi Lee BS, Kiel Hards K, Curtis A Engelhart CA, Erik J Hasenoehrl EJ, Nitin P Kalia NP, Jared S Mackenzie JS, Ekaterina Sviriaeva E, Shi Min Sherilyn Chong SMS, Malathy Sony S Manimekalai MSS, Vanessa H Koh VH, John Chan J, Jiayong Xu J, Sylvie Alonso S, Marvin J Miller MJ, Adrie J C Steyn AJC, Gerhard Gr├╝ber G, Dirk Schnappinger D, Michael Berney M, Gregory M Cook GM, Garrett C Moraski GC, Kevin Pethe K

The approval of bedaquiline has placed energy metabolism in the limelight as an attractive target space for tuberculosis antibiotic development. While bedaquiline inhibits the mycobacterial F F ATP synthase, small molecules targeting other components of the oxidative phosphorylation pathway have been identified. Of particular interest is Telacebec (Q203), a phase 2 drug candidate inhibitor of the cytochrome bcc:aa terminal oxidase. A functional redundancy between the cytochrome bcc:aa and the cytochrome bd oxidase protects M. tuberculosis from Q203-induced death, highlighting the attractiveness of the bd-type terminal oxidase for drug development. Here, we employed a facile whole-cell screen approach to identify the cytochrome bd inhibitor ND-011992. Although ND-011992 is ineffective on its own, it inhibits respiration and ATP homeostasis in combination with Q203. The drug combination was bactericidal against replicating and antibiotic-tolerant, non-replicating mycobacteria, and increased efficacy relative to that of a single drug in a mouse model. These findings suggest that a cytochrome bd oxidase inhibitor will add value to a drug combination targeting oxidative phosphorylation for tuberculosis treatment.

Courtesy of the U.S. National Library of Medicine