Transcriptional adaptation of drug-tolerant Mycobacterium tuberculosis during treatment of human tuberculosis

Nicholas D Walter, Gregory M Dolganov, Benjamin J Garcia, William Worodria, Alfred Andama, Emmanuel Musisi, Irene Ayakaka, Tran T Van, Martin I Voskuil, Bouke C de Jong, Rebecca M Davidson, Tasha E Fingerlin, Katerina Kechris, Claire Palmer, Payam Nahid, Charles L Daley, Mark Geraci, Laurence Huang, Adithya Cattamanchi, Michael StrongGary K Schoolnik, John Lucian Davis

Research output: Contribution to journalA1: Web of Science-articlepeer-review

40 Downloads (Pure)


BACKGROUND:  Treatment initiation rapidly kills most drug-susceptible Mycobacterium tuberculosis, but a bacterial subpopulation tolerates prolonged drug exposure. We evaluated drug-tolerant bacilli in human sputum by comparing messenger RNA (mRNA) expression of drug-tolerant bacilli that survive the early bactericidal phase with treatment-naive bacilli.

METHODS:  M. tuberculosis gene expression was quantified via reverse-transcription polymerase chain reaction in serial sputa from 17 Ugandans treated for drug-susceptible pulmonary tuberculosis.

RESULTS:  Within 4 days, bacterial mRNA abundance declined >98%, indicating rapid killing. Thereafter, the rate of decline slowed >94%, indicating drug tolerance. After 14 days, 16S ribosomal RNA transcripts/genome declined 96%, indicating slow growth. Drug-tolerant bacilli displayed marked downregulation of genes associated with growth, metabolism, and lipid synthesis and upregulation in stress responses and key regulatory categories-including stress-associated sigma factors, transcription factors, and toxin-antitoxin genes. Drug efflux pumps were upregulated. The isoniazid stress signature was induced by initial drug exposure, then disappeared after 4 days.

CONCLUSIONS:  Transcriptional patterns suggest that drug-tolerant bacilli in sputum are in a slow-growing, metabolically and synthetically downregulated state. Absence of the isoniazid stress signature in drug-tolerant bacilli indicates that physiological state influences drug responsiveness in vivo. These results identify novel drug targets that should aid in development of novel shorter tuberculosis treatment regimens.

Original languageEnglish
JournalJournal of Infectious Diseases
Issue number6
Pages (from-to)990-998
Number of pages9
Publication statusPublished - 2015


Dive into the research topics of 'Transcriptional adaptation of drug-tolerant Mycobacterium tuberculosis during treatment of human tuberculosis'. Together they form a unique fingerprint.

Cite this