Pyrazinamidase activity in clinical isolates of Mycobacterium tuberculosis has been previously found to correlate with susceptibility to the antituberculosis drug pyrazinamide. The Wayne method for determining pyrazinamidase activity, a technique also utilized as an aid in identification of mycobacteria, and thin-layer chromatography method were found to be useful screening methods for suscepti...

INTRODUCTION Proportion method is the most widely used susceptibility test and is considered the reference method for M.tuberculosis (2). When adopted to slow growing strains, such as M. bovis, it couldn’t produce results on time. In addition, this method cannot be applied to pyrazinamidase activity test (PZAase test), which is used to differentiate between M. bovis and M. bovis subsp. caprae (...

Pyrazinamide (PZA) is a first-line antituberculosis (anti-TB) drug capable of killing nonreplicating, persistent Mycobacterium tuberculosis. However, reliable testing of the susceptibility of M. tuberculosis to PZA is challenging. Using 432 clinical M. tuberculosis isolates, we compared the performances of five methods for the determination of M. tuberculosis susceptibility to PZA: the MGIT 960...

Testing the pyrazinamide (PZA) susceptibility of Mycobacterium tuberculosis isolates is challenging. In a previous paper, we described the development of a rapid colorimetric test for the PZA susceptibility of M. tuberculosis by a PCR-based in vitro-synthesized-pyrazinamidase (PZase) assay. Here, we present an integrated approach to detect M. tuberculosis and PZA susceptibility directly from sp...

Nicotinamidases catalyze the hydrolysis of nicotinamide to nicotinic acid and ammonia, an important reaction in the NAD(+) salvage pathway. This paper reports a new nicotinamidase from the deep-sea extremely halotolerant and alkaliphilic Oceanobacillus iheyensis HTE831 (OiNIC). The enzyme was active towards nicotinamide and several analogues, including the prodrug pyrazinamide. The enzyme was m...

Pyrazinamide (PZA) is an important first-line anti-tuberculosis drug. But PZA susceptibility test is challenging because PZA activity is optimal only in an acid environment that inhibits the growth of M. tuberculosis. For current phenotypic methods, inconsistent results between different labs have been reported. Direct sequencing of pncA gene is being considered as an accurate predictor for PZA...

BackgroundMultidrug-resistant tuberculosis (MDR-TB) patients have been suffering long, ineffective, and toxic treatment until short-course injectable-free regimens emerged. However, the new WHO-recommended might be less feasible in real-world setting. Here, we evaluated two optimized all-oral China.MethodsFrom April 2019 to August 2020, conducted a prospective nonrandomized controlled trial con...

The potential for drug-drug interactions mediated by the inhibition of cytochrome P-450 (CYP) were concerned during antituberculosis therapy. However, the information regarding human CYP inhibition by antituberculosis drugs is limited to isoniazid. In the current study, we examined the inhibitory effects of pyrazinamide and ethionamide, both of which are chemically related to isoniazid, on the ...

Pyrazinamidase of Mycobacterium tuberculosis catalyzes the conversion of pyrazinamide to the active molecule pyrazinoic acid. Reduction of pyrazinamidase activity results in a level of pyrazinamide resistance. Previous studies have suggested that pyrazinamidase has a metal-binding site and that a divalent metal cofactor is required for activity. To determine the effect of divalent metals on the...