Results
Title

Conditional Silencing by CRISPRi Reveals the Role of DNA Gyrase in Formation of Drug-Tolerant Persister Population in Mycobacterium tuberculosis.

Authors

Choudhary, Eira; Sharma, Rishabh; Kumar, Yashwant; Agarwal, Nisheeth

Abstract

Drug tolerance in mycobacterial pathogens is a global concern. Fluoroquinolone (FQ) treatment is widely used for induction of persisters in bacteria. Although FQs that target DNA gyrase are currently used as second-line anti-tuberculosis (TB) drugs, little is known about their impact on Mycobacterium tuberculosis (Mtb) persister formation. Here we explored the CRISPRi-based genetic repression for better understanding the effect of DNA gyrase depletion on Mtb physiology and response to anti-TB drugs. We find that suppression of DNA gyrase drastically affects intra- and extracellular growth of Mtb. Interestingly, gyrase depletion in Mtb leads to activation of RecA/LexA-mediated SOS response and drug tolerance via induction of persister subpopulation. Chemical inhibition of RecA in gyrase-depleted bacteria results in reversion of persister phenotype and better killing by antibiotics. This study provides evidence that inhibition of SOS response can be advantageous in improving the efficacy of anti-TB drugs and shortening the duration of current TB treatment.

Subjects

DNA topoisomerase II; MYCOBACTERIUM tuberculosis; DRUG tolerance; DRUG efficacy; RESPONSE inhibition

Publication

Frontiers in Cellular & Infection Microbiology, 2019, Vol 9, pN.PAG

ISSN

2235-2988

Publication type

Academic Journal

DOI

10.3389/fcimb.2019.00070