Abstract
Pyrazinamide (PZA) is a first-line tuberculosis drug that plays a unique role in shortening the duration of tuberculosis chemotherapy. PZA is hydrolyzed intracellularly to pyrazinoic acid (POA) by pyrazinamidase (PZase, encoded by pncA), an enzyme frequently lost in PZA-resistant strains, but the target of POA in Mycobacterium tuberculosis has remained elusive. Here, we identify a previously unknown target of POA as the ribosomal protein S1 (RpsA), a vital protein involved in protein translation and the ribosome-sparing process of trans-translation. Three PZA-resistant clinical isolates without pncA mutation harbored RpsA mutations. RpsA overexpression conferred increased PZA resistance, and we confirmed that POA bound to RpsA (but not a clinically identified ΔAla mutant) and subsequently inhibited trans-translation rather than canonical translation. Trans-translation is essential for freeing scarce ribosomes in nonreplicating organisms, and its inhibition may explain the ability of PZA to eradicate persisting organisms.
Original language | English (US) |
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Pages (from-to) | 1630-1632 |
Number of pages | 3 |
Journal | Science |
Volume | 333 |
Issue number | 6049 |
DOIs | |
State | Published - Sep 16 2011 |
Externally published | Yes |
ASJC Scopus subject areas
- General