keyword
MENU ▼
Read by QxMD icon Read
search

rpoB mutation

keyword
https://www.readbyqxmd.com/read/28633695/how-should-discordance-between-molecular-and-growth-based-assays-for-rifampicin-resistance-be-investigated
#1
S Hofmann-Thiel, H Hoffmann, D Hillemann, L Rigouts, A Van Deun, K Kranzer
Molecular tests to detect the presence of Mycobacterium tuberculosis and genetic polymorphisms in the rpoB gene conferring resistance to rifampicin (RMP) have become integral parts of tuberculosis diagnostics worldwide. These assays are often performed sequentially or in parallel to phenotypic drug susceptibility testing. Discordances between molecular and phenotypic tests invariably occur. Root causes range from pre-, post- and analytic errors to co-existence of non-tuberculous mycobacteria, silent mutations, mutations outside the 81 base-pair RMP resistance-determining region, non-canonical mutations conferring increased minimal inhibitory concentrations below the critical concentration in some phenotypic drug susceptibility tests, and heteroresistance...
July 1, 2017: International Journal of Tuberculosis and Lung Disease
https://www.readbyqxmd.com/read/28631643/multidrug-resistant-tuberculosis-detection-and-characterization-of-mutations-in-mycobacterium-tuberculosis-by-genotype-mtbdrplus
#2
Rajneesh Tripathi, Shampa Anupurba
Detection of drug resistance in Mycobacterium tuberculosis by conventional phenotypic drug susceptibility testing methods requires several weeks. Therefore, molecular diagnostic tests for rapid detection of multidrug resistance tuberculosis (MDR-TB) are urgently needed. Early diagnosis helps in initiating optimal treatment which would not only enable cure of an individual patient but also will curb the transmission of drug resistance in the community. Line probe assay (LPA) has shown great promises in the diagnosis of MDR-TB...
April 2017: Indian Journal of Pathology & Microbiology
https://www.readbyqxmd.com/read/28627432/high-diversity-of-multidrug-resistant-mycobacterium-tuberculosis-central-asian-strain-isolates-in-nepal
#3
Yogendra Shah, Bhagwan Maharjan, Jeewan Thapa, Ajay Poudel, Hassan Mahmoud Diab, Basu Dev Pandey, Eddie Solo, Norikazu Isoda, Yasuhiko Suzuki, Chie Nakajima
OBJECTIVES: Tuberculosis caused by Mycobacterium tuberculosis (MTB) poses a major public health problem in Nepal. Although it has been reported as one of the dominant genotypes of MTB in Nepal, little information on the Central Asian Strain (CAS) family is available, especially isolates related to multidrug resistance (MDR) cases. Here, we aimed to elucidate the genetic and epidemiological characteristics of MDR CAS isolates in Nepal. METHODS: A total of 145 MDR CAS isolates collected in Nepal from 2008 to 2013 were characterized by spoligotyping, mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) analysis and drug resistance-associating gene sequencing...
June 13, 2017: International Journal of Infectious Diseases: IJID
https://www.readbyqxmd.com/read/28627431/evaluation-of-the-quantamatrix-multiplexed-assay-platform-system-for-simultaneous-detection-of-mycobacteirum-tuberculosis-and-rifampicin-resistance-gene-using-culture-positive-mycobacteria
#4
Hye-Young Wang, Young Uh, Seoyong Kim, Tae-Sun Shim, Hyeyoung Lee
BACKGROUND: The differentiation of Mycobacterium tuberculosis complex (MTBC) from nontuberculous mycobacteria (NTM) is of primary importance for infection control and choice of anti-tuberculosis drugs. Prevailing data on rifampicin (RIF)-resistant TB is essential for early management of multidrug resistant-TB. The aim of this study was to evaluate the usefulness of a newly developed multiplexed, bead-based bioassay (Quantamatrix Multiplexed Assay Platform; QMAP) for the rapid differentiation of 23 Mycobacterium species including MTBC and RIF-resistant strains...
June 13, 2017: International Journal of Infectious Diseases: IJID
https://www.readbyqxmd.com/read/28623123/screening-mutations-in-drug-resistant-mycobacterium-tuberculosis-strains-in-yunnan-china
#5
Daoqun Li, Yuzhu Song, Cheng-Lin Zhang, Xiaofei Li, Xueshan Xia, A-Mei Zhang
Drug-resistant tuberculosis (DR-TB), especially multidrug-resistant tuberculosis (MDR-TB), is a serious medical and societal problem in China. The purpose of this study was to evaluate the mutation characteristics of drug-resistant Mycobacterium tuberculosis (M. tuberculosis) isolates in Yunnan, China. Drug susceptibility testing (DST) was performed in 523 clinical M. tuberculosis isolates. Six drug resistance genes (katG, inhA, rpoB, rpsL, embB, and pncA) were selected to screen for mutations. In total, 54 clinical M...
June 13, 2017: Journal of Infection and Public Health
https://www.readbyqxmd.com/read/28610794/molecular-mechanisms-of-action-resistance-detection-to-the-first-line-anti-tuberculosis-drugs-rifampicin-and-pyrazinamide-in-the-post-whole-genome-sequencing-era
#6
REVIEW
Ameeruddin Nusrath Unissa, Luke Elizabeth Hanna
Recent studies in addition to studies based on whole genome sequencing (WGS) of clinical isolates of Mycobacterium tuberculosis (MTB) from diverse geographical regions have provided useful insights into the mechanisms of drug resistance. Of importance, are some of the findings pertaining to mechanisms of resistance to two of the first-line anti-tuberculosis (TB) drugs, namely, rifampicin (RIF) and pyrazinamide (PZA). For example, the implication of mutations in rpoA and rpoC genes that act as compensatory mutations for those in the rpoB gene with respect to RIF resistance is noteworthy...
July 2017: Tuberculosis
https://www.readbyqxmd.com/read/28595277/genetic-alterations-responsible-for-reduced-susceptibility-to-vancomycin-in-community-associated-mrsa-strains-of-st72
#7
Jin Yang Baek, Doo Ryeon Chung, Kwan Soo Ko, So Hyun Kim, Soo-Jin Yang, Cheol-In Kang, Kyong Ran Peck, Jae-Hoon Song
Objectives: We previously reported the first case of vancomycin treatment failure due to development of vancomycin-intermediate resistance in a patient with an MRSA of ST72, a community genotype in Korea. We investigated two isogenic MRSA strains from this patient, who experienced treatment failure with vancomycin and rifampicin. Methods: We tracked the genetic alterations that confer reduced susceptibility to vancomycin on those two isogenic MRSA strains by WGS...
June 7, 2017: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/28569148/diagnostic-accuracy-and-usefulness-of-the-genotype-mtbdrplus-assay-in-diagnosing-multidrug-resistant-tuberculosis-in-cameroon-a-cross-sectional-study
#8
Ngu Njei Abanda, Josiane Yvonne Djieugoué, Eunjung Lim, Eric Walter Pefura-Yone, Wilfred Fon Mbacham, Guy Vernet, Veronique Mbeng Penlap, Sara Irene Eyangoh, Diane Wallace Taylor, Rose Gana Fomban Leke
BACKGROUND: Drug-resistant tuberculosis, especially multidrug-resistant tuberculosis (MDR-TB), is a major public health problem. Effective management of MDR-TB relies on accurate and rapid diagnosis. In this study, we assessed the diagnostic accuracy of the Genotype MTBDRplus assay in diagnosing MDR-TB in Cameroon, and then discuss on its utility within the diagnostic algorithm for MDR-TB. METHODS: In this cross-sectional study, 225 isolates of Mycobacterium tuberculosis cultured from sputum samples collected from new and previously treated pulmonary tuberculosis patients in Cameroon were used to determine the accuracy of the Genotype MTBDRplus assay...
May 31, 2017: BMC Infectious Diseases
https://www.readbyqxmd.com/read/28565846/use-of-dna-microarray-chips-for-the-rapid-detection-of-mycobacterium-tuberculosis-resistance-to-rifampicin-and-isoniazid
#9
Peijun Tang, Xiafang Wang, Xinghua Shen, Meihua Shi, Xuefeng Zhu, Xin Yu, Jia Liu, Chunhua Ling, Meiying Wu
The objective of the present study was to evaluate the potential development of DNA microarray chips to detect rifampicin (RFP) and isoniazid (INH) resistance in Mycobacterium tuberculosis (MTB), using samples from clinical tuberculosis (TB) patients in Soochow City, China. The sputum samples of 42 patients with TB in the Affiliated Hospital of Infectious Diseases of Soochow University (Soochow, China) were collected. The conventional Lowenstein-Jensen culture medium (Gold Standard) was used to assess drug sensitivity using the absolute concentration method...
May 2017: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/28559332/rifamycin-action-on-rna-polymerase-in-antibiotic-tolerant-mycobacterium-tuberculosis-results-in-differentially-detectable-populations
#10
Kohta Saito, Thulasi Warrier, Selin Somersan-Karakaya, Lina Kaminski, Jianjie Mi, Xiuju Jiang, Suna Park, Kristi Shigyo, Ben Gold, Julia Roberts, Elaina Weber, William R Jacobs, Carl F Nathan
Mycobacterium tuberculosis (Mtb) encounters stresses during the pathogenesis and treatment of tuberculosis (TB) that can suppress replication of the bacteria and render them phenotypically tolerant to most available drugs. Where studied, the majority of Mtb in the sputum of most untreated subjects with active TB have been found to be nonreplicating by the criterion that they do not grow as colony-forming units (cfus) when plated on agar. However, these cells are viable because they grow when diluted in liquid media...
June 13, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28545050/prevalence-and-extent-of-heteroresistance-by-next-generation-sequencing-of-multidrug-resistant-tuberculosis
#11
Darwin J Operario, Alexander F Koeppel, Stephen D Turner, Yongde Bao, Suporn Pholwat, Sayera Banu, Suporn Foongladda, Stellah Mpagama, Jean Gratz, Oleg Ogarkov, Svetlana Zhadova, Scott K Heysell, Eric R Houpt
Amplicon-based Next Generation Sequencing (NGS) is an emerging method for Mycobacterium tuberculosis drug susceptibility testing (DST) but has not been well described. We examined 158 clinical multidrug-resistant M. tuberculosis isolates via NGS of 11 resistance-associated gene regions covering 3519 nucleotides. Across these gene regions, complete resistance or heteroresistance (defined as 1%-99% mutation) was present in at least one isolate in 6.3% of loci. The number of isolates with heteroresistance was highest for gyrA codon 94, rpoB codons 526 and 531, and embB codons 306, 372 and 406 (range 11-26% of isolates exhibited heteroresistance)...
2017: PloS One
https://www.readbyqxmd.com/read/28533123/molecular-characterization-of-caulobacter-crescentus-mutator-strains
#12
Marinalva Martins-Pinheiro, Alice R Oliveira, Alexy O Valencia, Frank S Fernandez-Silva, Larissa G Silva, Carina O Lopes-Kulishev, Valeria C S Italiani, Marilis V Marques, Carlos F Menck, Rodrigo S Galhardo
Mutator strains were identified by screening random Tn5 insertion clones of Caulobacter crescentus. We identified clones with robust increases in mutation rates with Tn5 insertions in the mutY, mutS, mutL and uvrD genes, known to act in mutation-preventing pathways in Escherichia coli. Analysis of mutations in the rpoB gene revealed that in both the parental strain and mismatch repair-deficient mutants, A:T→G:C transitions predominate by a large margin over C:G→T:A. We have also investigated the role of the error-prone polymerase encoded by imuC (dnaE2) in spontaneous mutagenesis, and found that a imuC mutant strain shows mutation rates and sequences comparable to the parental strain...
May 19, 2017: Gene
https://www.readbyqxmd.com/read/28513421/clinical-and-bacteriological-characteristics-associated-with-clustering-of-multidrug-resistant-tuberculosis
#13
J-Y Feng, L G Jarlsberg, K Salcedo, J Rose, M Janes, S-Y G Lin, D H Osmond, K C Jost, M K Soehnlen, J Flood, E A Graviss, E Desmond, P K Moonan, P Nahid, P C Hopewell, M Kato-Maeda
SETTING: The impact of the genetic characteristics of Mycobacterium tuberculosis on the clustering of multidrug-resistant tuberculosis (MDR-TB) has not been analyzed together with clinical and demographic characteristics. OBJECTIVE: To determine factors associated with genotypic clustering of MDR-TB in a community-based study. DESIGN: We measured the proportion of clustered cases among MDR-TB patients and determined the impact of clinical and demographic characteristics and that of three M...
July 1, 2017: International Journal of Tuberculosis and Lung Disease
https://www.readbyqxmd.com/read/28511895/diagnostic-performance-of-anyplex-ii-mtb-mdr-xdr-for-detection-of-resistance-to-first-and-second-line-drugs-in-mycobacterium-tuberculosis
#14
F Pérez-García, M J Ruiz-Serrano, P López Roa, Fermín Acosta, Laura Pérez-Lago, D García-De-Viedma, E Bouza
PURPOSE: Genotypic methods have considerably improved the diagnosis of multidrug-resistant (MDR) tuberculosis. One of these tests is Anyplex II MTB/MDR/XDR (Anyplex). Our aim was to evaluate the diagnostic performance of this multiplex PCR. METHODS: We conducted our study on 47 MDR tuberculosis and 14 pan-susceptible strains. We evaluated the ability of Anyplex to detect resistance mutations in rpoB (rifampin [RIF]), katG and inhA (isoniazid [INH]), gyrA (fluoroquinolones [FLQ]), and rrs and eis (aminoglycosides [AMG])...
May 13, 2017: Journal of Microbiological Methods
https://www.readbyqxmd.com/read/28507065/mutants-in-the-%C3%AE-subunit-of-the-rna-polymerase-impairing-the-surface-associated-motility-and-virulence-of-acinetobacter-baumannii
#15
María Pérez-Varela, Jordi Corral, Juan Andrés Vallejo, Soraya Rumbo-Feal, Germán Bou, Jesús Aranda, Jordi Barbé
Acinetobacter baumannii is a major cause of antibiotic-resistant nosocomial infections worldwide. In this study, several rifampin-resistant spontaneous mutants obtained from the A. baumannii ATCC 17978 strain were isolated that differed in their point mutations in the rpoB gene, encoding the β-subunit of the RNA polymerase. All mutants harboring amino acid substitutions in positions 522 or 540 of the RpoB protein were impaired in surface-associated motility and had attenuated virulence in the fertility model of Caenorhabditis elegans The transcriptional profile of these mutants included six down-regulated genes encoding proteins homologous to transporters and metabolic enzymes widespread among A...
May 15, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/28485504/mechanistic-principles-behind-molecular-mechanism-of-rifampicin-resistance-in-mutant-rna-polymerase-beta-subunit-of-mycobacterium-tuberculosis
#16
Aditi Singh, Sonam Grover, Sidhartha Sinha, Mriganko Das, Pallavi Somvanshi, Abhinav Grover
Evolution of drug resistant Mycobacterium strains threatens the TB treatment and control programs globally. Rifampicin (RIF) is an important first line antitubercular drug. Resistance to Rifampicin is caused mainly by mutations in its target RNA polymerase beta subunit protein (RpoB). RpoB contains a Rifampicin resistance determining region (RRDR) and has several potent sites for mutations. In this study, we have investigated mutations of a single site (H451) to eight different amino acids, involved in RIF resistance...
May 9, 2017: Journal of Cellular Biochemistry
https://www.readbyqxmd.com/read/28472124/performance-of-taqman-array-card-to-detect-tb-drug-resistance-on-direct-specimens
#17
Sayera Banu, Suporn Pholwat, Suporn Foongladda, Rattapha Chinli, Duangjai Boonlert, Sara Sabrina Ferdous, S M Mazidur Rahman, Arfatur Rahman, Shahriar Ahmed, Eric R Houpt
Culture based phenotypic drug susceptibility testing (DST) for Mycobacterium tuberculosis (TB) is time consuming therefore rapid genotypic methods are increasingly being utilized. We previously developed and evaluated on TB isolates a rapid genotypic TaqMan array card (TAC) that detects mutations in several resistance-associated genes using dozens of primer pairs, probes, and high resolution melt analysis, with >96% accuracy versus Sanger sequencing. In this study we examined the performance of TAC on sputum, comparing results between 71 paired sputum and TB isolates of which 62 were MDR-TB...
2017: PloS One
https://www.readbyqxmd.com/read/28456705/positive-epistasis-of-major-low-cost-drug-resistance-mutations-rpob531-ttg-and-katg315-acc-depends-on-the-phylogenetic-background-of-mycobacterium-tuberculosis-strains
#18
Qin-Jing Li, Wei-Wei Jiao, Qing-Qin Yin, Ying-Jia Li, Jie-Qiong Li, Fang Xu, Lin Sun, Jing Xiao, Hui Qi, Ting Wang, Igor Mokrousov, Hai-Rong Huang, A-Dong Shen
Mycobacterium tuberculosis Beijing genotype strains increasingly circulate in different world regions, either as historical endemic, e.g. in East Asia, or recently imported, e.g. in South America, and this family is regarded as the most successful lineage of the global tuberculosis (TB) epidemic. Here we analysed the transmission capacity of these strains in the context of their phylogenetic background and drug resistance mutations. The study collection included all multidrug resistant (MDR) strains of Beijing genotype isolated in Beijing Chest Hospital, the largest tertiary TB facility in North China, in 2011-2013 (n = 278)...
June 2017: International Journal of Antimicrobial Agents
https://www.readbyqxmd.com/read/28442708/the-complete-12%C3%A2-mb-genome-and-transcriptome-of-nonomuraea-gerenzanensis-with-new-insights-into-its-duplicated-magic-rna-polymerase
#19
Valeria D'Argenio, Mauro Petrillo, Daniela Pasanisi, Caterina Pagliarulo, Roberta Colicchio, Adelfia Talà, Maria Stella de Biase, Mario Zanfardino, Emanuela Scolamiero, Chiara Pagliuca, Antonio Gaballo, Annunziata Gaetana Cicatiello, Piergiuseppe Cantiello, Irene Postiglione, Barbara Naso, Angelo Boccia, Miriana Durante, Luca Cozzuto, Paola Salvatore, Giovanni Paolella, Francesco Salvatore, Pietro Alifano
In contrast to the widely accepted consensus of the existence of a single RNA polymerase in bacteria, several actinomycetes have been recently shown to possess two forms of RNA polymerases due the to co-existence of two rpoB paralogs in their genome. However, the biological significance of the rpoB duplication is obscure. In this study we have determined the genome sequence of the lipoglycopeptide antibiotic A40926 producer Nonomuraea gerenzanensis ATCC 39727, an actinomycete with a large genome and two rpoB genes, i...
December 21, 2016: Scientific Reports
https://www.readbyqxmd.com/read/28438132/early-detection-of-multidrug-and-pre-extensively-drug-resistant-tuberculosis-from-smear-positive-sputum-by-direct-sequencing
#20
Jun Chen, Peng Peng, Yixiang Du, Yi Ren, Lifeng Chen, Youyi Rao, Weihua Wang
BACKGROUND: Emergence of multidrug- and extensively drug-resistant tuberculosis (M/XDR-TB) is a major hurdle for TB control programs especially in developing countries like China. Resistance to fluoroquinolones is high among MDR-TB patients. Early diagnosis of MDR/pre-XDR-TB is essential for lowering transmission of drug-resistant TB and adjusting the treatment regimen. METHODS: Smear-positive sputum specimens (n = 186) were collected from Wuhan Institute for Tuberculosis Control...
April 24, 2017: BMC Infectious Diseases
keyword
keyword
95284
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"