Browse
Submit Data
Databases
API
Help

Dataset Information

21 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Diverse Clinical Isolates of Mycobacterium tuberculosis Develop Macrophage-Induced Rifampin Tolerance.

ABSTRACT: The Mycobacterium tuberculosis lineage 4 strains CDC1551 and H37Rv develop tolerance to multiple antibiotics upon macrophage residence. To determine whether macrophage-induced tolerance is a general feature of clinical M. tuberculosis isolates, we assessed macrophage-induced drug tolerance in strains from lineages 1-3, representing the other predominant M. tuberculosis strains responsible for tuberculosis globally. All 3 lineages developed isoniazid tolerance. While lineage 1, 3, and 4 strains developed rifampin tolerance, lineage 2 Beijing strains did not. Their failure to develop tolerance may be explained by their harboring of a loss-of-function mutation in the Rv1258c efflux pump that is linked to macrophage-induced rifampicin tolerance.

SUBMITTER: Adams KN

PROVIDER: S-EPMC6473171 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Characterization of Tunisian Mycobacterium tuberculosis rifampin-resistant clinical isolates.

Project description:Analysis of the gene encoding the beta-subunit of Mycobacterium tuberculosis RNA polymerase (rpoB) has demonstrated a small region that harbors the mutations most frequently associated with rifampin resistance. In this study, we determined the occurrence of rifampin resistance in 544 Tunisian clinical M. tuberculosis strains isolated in a university hospital between 2004 and 2006 by using the standard-proportion agar method, the INNO-LiPA Rif.TB assay, and DNA sequencing.

| S-EPMC2045245 | biostudies-literature

Mixed Infections and Rifampin Heteroresistance among Mycobacterium tuberculosis Clinical Isolates.

Project description:Mixed infections and heteroresistance of Mycobacterium tuberculosis contribute to the difficulty of diagnosis, treatment, and control of tuberculosis. However, there is still no proper solution for these issues. This study aimed to investigate the potential relationship between mixed infections and heteroresistance and to determine the high-risk groups related to these factors. A total of 499 resistant and susceptible isolates were subjected to spoligotyping and 24-locus variable-number tandem repeat methods to analyze their genotypic lineages and the occurrence of mixed infections. Two hundred ninety-two randomly selected isolates were sequenced on their rpoB gene to examine mutations and heteroresistance. The results showed that 12 patients had mixed infections, and the corresponding isolates belonged to Manu2 (n = 8), Beijing (n = 2), T (n = 1), and unknown (n = 1) lineages. Manu2 was found to be significantly associated with mixed infections (odds ratio, 47.72; confidence interval, 9.68 to 235.23; P < 0.01). Four isolates (1.37%) were confirmed to be heteroresistant, which was caused by mixed infections in three (75%) isolates; these belonged to Manu2. Additionally, 3.8% of the rifampin-resistant isolates showing no mutation in the rpoB gene were significantly associated with mixed infections (χ(2), 56.78; P < 0.01). This study revealed for the first time that Manu2 was the predominant group in the cases of mixed infections, and this might be the main reason for heteroresistance and a possible mechanism for isolates without any mutation in the rpoB gene to become rifampin resistant. Further studies should focus on this lineage to clarify its relevance to mixed infections.

| S-EPMC4473183 | biostudies-literature

Rapid determination of rifampin resistance in clinical isolates of Mycobacterium tuberculosis by real-time PCR.

Project description:Real-time PCR was used to determine rifampin resistance in clinical isolates of Mycobacterium tuberculosis. Ninety-six rifampin-resistant isolates and 23 rifampin-susceptible isolates were included in the study. A 305-bp region covering the 81-bp "rifampin resistance-determining region" of rpoB was amplified. Two hybridization probe pairs that covered the most frequent mutation sites in rpoB, codon regions 526 to 531 and 513 to 516, were used. The results obtained by real-time PCR were compared to those obtained by the proportion method. For detection of rifampin resistance, the real-time PCR assay yielded a sensitivity of 92.7% and a specificity of 100%. Real-time PCR is a very rapid method, and it can be especially helpful for the reporting of resistant clinical isolates in a very short period of time.

| S-EPMC1317190 | biostudies-literature

Transcriptome analysis of Mycobacterium tuberculosis clinical isolates.

Project description:Bacterial persister cells are phenotypic variants of regular cells that are tolerant to antibiotics. Analysis of clinical isolates of M. tuberculosis showed that strains vary substantially in their tolerance to antibiotics. The level of persisters was very high is some isolates, suggesting that these are hip mutants. We investigated gene expression differences in eight clinical isolates, four of which we characterized as high-persister strains and four as low-persister, or regular, strains. Comparison of gene expression patterns may provide clues as to the genetic mechanisms underlying persister formation.

2015-01-01 | GSE62025 | GEO

Gene expression diversity among Mycobacterium tuberculosis clinical isolates

Project description:While several groups, including our own, have examined variability of M. tuberculosis at the DNA level, this is the first systematic survey of variability in mRNA expression among clinical isolates of M. tuberculosis. Genes whose expression varies among isolates when assayed under a single growth condition may make poor drug targets and vaccine antigens and may affect molecular diagnostics, so they can be used to narrow down lists of candidate molecules. Because the measurement of gene expression is extremely sensitive to environmental conditions, comparison of gene expression is labour intensive. In this study, we surveyed 12 strains. These strains are a subset of those for which we have already published genomic deletion information (Kato-Maeda et al., 2001). In order to ensure maximum reproducibility of the experiments and avoid complications caused by differences in growth conditions, we measured gene expression under well-controlled in vitro conditions. Our aims were to provide an overview of gene expression variability among clinical isolates under a single growth condition and to test whether gene functional classes are related to variability in expression. Set of arrays that are part of repeated experiments Keywords: Biological Replicate

2005-08-26 | GSE3201 | GEO

Rapid detection of isoniazid, rifampin, and ofloxacin resistance in Mycobacterium tuberculosis clinical isolates using high-resolution melting analysis.

Project description:A high-resolution melting analysis (HRMA) assay was developed to detect isoniazid, rifampin, and ofloxacin resistance in Mycobacterium tuberculosis by targeting resistance-associated mutations in the katG, mabA-inhA promoter, rpoB, and gyrA genes. A set of 28 (17 drug-resistant and 11 fully susceptible) clinical M. tuberculosis isolates was selected for development and evaluation of HRMA. PCR amplicons from the katG, mabA-inhA promoter, rpoB, and gyrA genes of all 28 isolates were sequenced. HRMA results matched well with 18 mutations, identified by sequencing, in 17 drug-resistant isolates and the absence of mutations in 11 susceptible isolates. Among 87 additional isolates with known resistance phenotypes, HRMA identified katG and/or mabA-inhA promoter mutations in 66 of 69 (95.7%) isoniazid-resistant isolates, rpoB mutations in 51 of 54 (94.4%) rifampin-resistant isolates, and gyrA mutations in all of 41 (100%) ofloxacin-resistant isolates. All mutations within the HRMA primer target regions were detected as variant HRMA profiles. The corresponding specificities were 97.8%, 100%, and 98.6%, respectively. Most false-positive results were due to synonymous mutations, which did not affect susceptibility. HRMA is a rapid, sensitive method for detection of drug resistance in M. tuberculosis which could be used routinely for screening isolates in countries with a high prevalence of tuberculosis and drug resistance or in individual isolates when drug resistance is suspected.

| S-EPMC3187326 | biostudies-literature

High-resolution melting curve analysis for rapid detection of rifampin and isoniazid resistance in Mycobacterium tuberculosis clinical isolates.

Project description:We evaluated high-resolution melting (HRM) curve analysis as a tool for detecting rifampin (RIF) and isoniazid (INH) resistance in Mycobacterium tuberculosis in an accurate, affordable, and rapid manner. Two hundred seventeen M. tuberculosis clinical isolates of known resistance phenotype were used. Twenty-nine known rpoB mutant DNAs, including rare mutations, were also included. Four pairs of primers were designed: rpoB-F/R (for codons 516 to 539 of rpoB), rpoB-516F/R (for codons 508 to 536 of rpoB), katG-F/R (for the codon 315 region of katG), and inhA-F/R (for the nucleotide substitution of C to T at position -15 of inhA). An HRM curve was generated for each isolate after real-time PCR differentiated the mutant from the wild-type strains. DNA sequencing of the target regions was performed to confirm the results of the HRM curve analysis. All but one of the 73 RIF-resistant (RIF-R) strains and all 124 RIF-susceptible (RIF-S) isolates were correctly identified by HRM curve analysis of rpoB. Twenty-seven of 29 known rpoB mutants were detected. In HRM curve analysis of katG and inhA, 90 INH-R strains that harbored katG or inhA mutations, or both, and all INH-S strains were correctly identified. Ten phenotypically INH-R strains not harboring katG or inhA mutations were not detected. The HRM curve analysis will be a useful method for detection of RIF and INH resistance in M. tuberculosis in a rapid, accurate, simple, and cost-effective manner.

| S-EPMC3020879 | biostudies-literature

Frequency of rpoB mutations inside and outside the cluster I region in rifampin-resistant clinical Mycobacterium tuberculosis isolates.

Project description:The prevalence of recently described mutation V176F, located in the beginning of the rpoB gene and associated with rifampin resistance and the wild-type cluster I sequence, was determined by analyzing the distribution of rpoB mutations among 80 rifampin (RIF)-resistant Mycobacterium tuberculosis strains isolated in Germany during 1997. The most frequent rpoB mutations were changes in codon 456 (52 isolates, 65%), followed by changes in codon 441 (13 isolates, 16%) and codon 451 (11 isolates, 14%). The V176F mutation was detected in one isolate of the study population and in 5 of 18 RIF-resistant strains with no cluster I mutation from six previously published studies. In three isolates, a mixture of resistant and susceptible subpopulations (heteroresistance) prohibited the detection of rpoB mutations in the initial analysis; however, in these isolates, cluster I mutations could be verified after a passage on RIF-containing medium. IS6110 DNA fingerprinting of 76 strains revealed eight clusters comprising 27 strains with identical restriction fragment length polymorphism patterns that mainly also show identical rpoB mutations and identical or similar drug resistance patterns. In conclusion, our results indicate that the V176F mutation should be included in molecular tests for prediction of RIF resistance in M. tuberculosis. We further demonstrated that heteroresistance caused by a mixture of mycobacterial subpopulations with different susceptibilities to RIF may influence the sensitivity of molecular tests for detection of resistance.

| S-EPMC87688 | biostudies-literature

Gene expression diversity among Mycobacterium tuberculosis clinical isolates

2005-08-26 | E-GEOD-3201 | biostudies-arrayexpress

Transcription profiling of Mycobacterium tuberculosis 12 clinical isolates

Project description:Protocol Name

2005-08-23 | E-SMDB-2885 | biostudies-arrayexpress