Kazakhstan is one of the 14 countries with a high rate of morbidity due to multidrug-resistant tuberculosis (MDR TB) in WHO European region. The aim of our study was to characterize mutations associated with drug resistance to rifampicin and isoniazid in Mycobacterium tuberculosis isolates from Kazakhstan. M. tuberculosis strains were isolated from TB patients in different regions of Kazakhstan...

OBJECTIVE To analyze and compare the mutations in two different regions of the katG gene, which is responsible for isoniazid (INH) resistance. METHODS We analyzed 97 multidrug-resistant Mycobacterium tuberculosis strains isolated in cultures of sputum samples obtained from the Professor Hélio Fraga Referral Center, in Brasília, Brazil. Another 6 INH-sensitive strains did not present mutations...

Nitrogen-fixing bacteria collectively called rhizobia are adapted to live in polyphenol-rich environments. The mechanisms that allow these bacteria to overcome toxic concentrations of plant polyphenols have not been clearly elucidated. We used a crude extract of polyphenols released from the seed coat of the black bean to simulate a polyphenol-rich environment and analyze the response of the be...

Catalase-peroxidase (KatG) is an enzyme capable of utilizing both catalase and peroxidase activity to break down hydrogen peroxide. Catalase activity by the enzyme generally dominates, but peroxidatic electron donors have been shown to stimulate catalase activity, likely by rescuing catalase-inactive intermediates resulting from off-pathway electron transfer. To investigate tryptophan 438 as a ...

OBJECTIVE To assess the efficacy of a line-probe assay delta (LiPA) as rapid diagnostic test for early detection of drug-resistant tuberculosis compared to conventional susceptibility methods in Pakistan. METHODS Resistance to rifampicin (RIF) and isoniazid (INH) in 108 smear-positive pulmonary tuberculosis samples was detected using a line-probe assay [GenoType MTBDRplus (Hain Lifescience, G...

A novel protocol for full-length Mycobacterium tuberculosis gene analysis of first- and second-line drug resistance was developed using the Ion Torrent Personal Genome Machine (PGM). Five genes-rpoB (rifampin), katG (isoniazid), pncA (pyrazinamide), gyrA (ofloxacin/fluoroquinolone), and rrs (aminoglycosides)-were amplified and sequenced, and results were compared to those obtained by genotypic ...

BACKGROUND Improving our understanding of the relationship between the genotype and the drug resistance phenotype of Mycobacterium tuberculosis will aid the development of more accurate molecular diagnostics for drug-resistant tuberculosis. Studies that use direct genetic manipulation to identify the mutations that cause M. tuberculosis drug resistance are superior to associational studies in e...

It has been suggested that catalase-peroxidase plays an important role in several aspects of mycobacterial metabolism and is a virulence factor in the main pathogenic mycobacteria. In this investigation, we studied genes encoding for this protein in the fast-growing opportunistic pathogen Mycobacterium fortuitum. Nucleotide sequences of two different catalase-peroxidase genes (katGI and katGII)...

OBJECTIVES Multidrug-resistant tuberculosis (MDR-TB) is a global problem that many countries are challenged with. Rapid and accurate detection of MDR-TB is critical for appropriate treatment and controlling of TB. The aim of the present study was to evaluate the TaqMan allelic discrimination without minor groove binder (MGB) as a rapid, efficient, and low-cost method for detection of drug resis...