OBJECTIVES The aim of this study was to compare the efficiency of two commercial assays, INNO-LiPA Rif.TB and MTBDRplus, for the identification of mutations in the rpoB hot-spot region and to assess the efficiency of these mutations in conferring resistance to rifampicin. METHODS A collection of 126 rifampicin-resistant Mycobacterium tuberculosis and Mycobacterium africanum isolates and 18 ri...

The World Health Organization has recommended use of molecular-based tests MTBDRplus and GeneXpert MTB/RIF to diagnose multidrug-resistant tuberculosis in developing and high-burden countries. Both tests are based on detection of mutations in the Rifampin (RIF) Resistance-Determining Region of DNA-dependent RNA Polymerase gene (rpoB). Such mutations are found in 95-98% of Mycobacterium tubercul...

UV-induced mutation frequency and cell survivability was examined in Escherichia coli K12 strains. The effects of UV (254nm) induced damage on deoxyribonucleic acid (DNA) was investigated using two protocols termed Direct-Plate Irradiation (DPI) and Liquid-Plate Irradiation (LPI). A biological system needed to be designed to facilitate future experiments involving UV and gene mutation frequenci...

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 ...

We report the first Korean case of lung diseases caused by Mycobacterium abscessus subsp. bolletii in a previously healthy male, except for a previous history of pulmonary tuberculosis and bronchiectasis. All serial isolates are identified as M. abscessus subsp. bolletii by multi-locus sequence analysis based on the hsp65, rpoB, and 16S rRNA fragments. At the genetic level, the isolate has the ...

Fitness tradeoffs are often assumed by evolutionary theory, yet little is known about the frequency of fitness tradeoffs during stress adaptation. Even less is known about the genetic factors that confer these tradeoffs and whether alternative adaptive mutations yield contrasting tradeoff dynamics. We addressed these issues using 114 clones of Escherichia coli that were evolved independently fo...

In the Netherlands, clinical isolation of nontuberculous mycobacteria (NTM) has increased over the past decade. Proper identification of isolates is important, as NTM species differ strongly in clinical relevance. Most of the currently applied identification methods cannot distinguish between all different Mycobacterium species and complexes within species. rpoB gene sequencing exhibits a promi...

background co-infection with human immunodeficiency virus (hiv) and hepatitis b virus (hbv) is common due to shared routes of transmission, as reported approximately 10% of 33 million hiv-infected patients worldwide are chronically infected with hbv. mutations of hbsag especially within the “a” determinant could alter the antigenicity of the protein, causing failure of hbsag neutralization and ...

High-density oligonucleotide arrays can be used to rapidly examine large amounts of DNA sequence in a high throughput manner. An array designed to determine the specific nucleotide sequence of 705 bp of the rpoB gene of Mycobacterium tuberculosis accurately detected rifampin resistance associated with mutations of 44 clinical isolates of M. tuberculosis. The nucleotide sequence diversity in 121...

OBJECTIVES Ontario bears the greatest burden of tuberculosis in Canada, with 40% of all cases and 60% of multidrug-resistant cases. The purpose of this study was to genotypically characterize isoniazid- and rifampicin-resistant isolates and compare these results with phenotypic drug susceptibility testing data. This is the first Canadian study to examine gene mutations that contribute to multid...