期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2017
卷号：114
期号：28
页码：7426-7431
DOI：10.1073/pnas.1706139114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The recent discovery of small molecules targeting the cytochrome bc 1 : aa 3 in Mycobacterium tuberculosis triggered interest in the terminal respiratory oxidases for antituberculosis drug development. The mycobacterial cytochrome bc 1 : aa 3 consists of a menaquinone:cytochrome c reductase ( bc 1 ) and a cytochrome aa 3 -type oxidase. The clinical-stage drug candidate Q203 interferes with the function of the subunit b of the menaquinone:cytochrome c reductase. Despite the affinity of Q203 for the bc 1 : aa 3 complex, the drug is only bacteriostatic and does not kill drug-tolerant persisters. This raises the possibility that the alternate terminal bd -type oxidase (cytochrome bd oxidase) is capable of maintaining a membrane potential and menaquinol oxidation in the presence of Q203. Here, we show that the electron flow through the cytochrome bd oxidase is sufficient to maintain respiration and ATP synthesis at a level high enough to protect M. tuberculosis from Q203-induced bacterial death. Upon genetic deletion of the cytochrome bd oxidase-encoding genes cydAB , Q203 inhibited mycobacterial respiration completely, became bactericidal, killed drug-tolerant mycobacterial persisters, and rapidly cleared M. tuberculosis infection in vivo. These results indicate a synthetic lethal interaction between the two terminal respiratory oxidases that can be exploited for anti-TB drug development. Our findings should be considered in the clinical development of drugs targeting the cytochrome bc 1 : aa 3 , as well as for the development of a drug combination targeting oxidative phosphorylation in M. tuberculosis .
