What does rpoB gene do?
Some bacteria contain multiple copies of the 16S rRNA gene, which is commonly used as the molecular marker to study phylogeny. In these cases, the rpoB gene can be used to study microbial diversity.
What caused the rpoB mutation?
Based on the previous reports, rifampin resistance (more than 95%) was caused by at least a mutation in the RRDR of β-subunit of RNA polymerase (rpoB) gene. This achievement showed that the mutations in codon 531 followed by codon 526 and codon 516 were the most frequent mutations in RRDR of the rpoB gene (15, 16).
How long is the rpoB gene?
The rpoB gene extends from 3411 bp (Staphylococcus aureus) to 4185 bp (Neisseria meningitidis) and is a monocopy gene, with the exception of that present in the RIF-R Nocardia farcinica strain .
What is IS6110?
IS6110 is an insertion element found exclusively within the members of the Mycobacterium tuberculosis complex (MTBC), and because of this exclusivity, it has become an important diagnostic tool in the identification of MTBC species.
What is rifampicin resistance?
Rifampicin-resistant TB (RR-TB) defined as resistance to rifampicin detected using genotypic or phenotypic methods with or without resistance to other first-line anti-TB drugs. MDR-TB/RR-TB has been an area of growing concern to human health worldwide and posing a threat to the control of TB.
What is rpoB gene sequencing?
Sequencing of rpoB enables efficient estimation of bacterial G+C% content, DNA-DNA hybridization value and average nucleotide identity (percentage of the total genomic sequence shared between two strains) when taxonomic relationships have been firmly established.
How does rifampicin inhibit transcription?
Rifampicin binds to the exit channel of the RNA polymerase by making specific contacts that involve the β-subunit of RNA polymerase. Rifampicin blocks the exit channel thereby inhibiting transcription (Campbell et al., 2001). Thus, runoff transcription continues after the addition of rifampicin.
Is 6110 a gene?
IS6110 is an insertion element that is found exclusively within the MTBC; the assumption has been that this restriction is a result of the lack of genetic exchange with other mycobacterial species.
Is insertion a sequence?
Insertion element (also known as an IS, an insertion sequence element, or an IS element) is a short DNA sequence that acts as a simple transposable element. The coding region in an insertion sequence is usually flanked by inverted repeats.
What causes rifampicin resistance?
Rifampicin, as the most effective first-line antituberculosis drug, also develops resistance due to the mutation on Mycobacterium tuberculosis (Mtb) RNA polymerase.
Is E coli resistance to rifampicin?
coli clones exhibited resistance to rifampicin. Twelve of these 13 clones included a mutation in codon 572 of the rpoB gene, with three different mutations observed in that codon (Table 1). These three mutations have been noted previously to confer rifampicin resistance , a finding we have reconfirmed.
How is the rpoB gene used in microbiology?
For Staphylococcus aureus, the rifamycin-resistant mutation most commonly encountered involves codon 526. Some bacteria contain multiple copies of the 16S rRNA gene, which is commonly used as the molecular marker to study phylogeny. In these cases, the rpoB gene can be used to study microbial diversity.
How are bacteria resistant to rifampicin and rpoB mutations?
Bacteria with mutations in the proper loci along the rpoB gene are resistant to this effect. Initial studies were done by Jin and Gross to generate rpoB mutations in E. coli that conferred resistance to rifampicin. Three clusters of mutations were identified, cluster I at codons 507-533, cluster II at codons 563-572, and cluster III at codon 687.
What kind of drug is Mycobacterium tuberculosis resistant to?
The determination of drug susceptibility is particularly relevant because Mycobacterium tuberculosis becomes increasingly resistant to two of the major anti-tuberculosis drugs, isoniazide and rifampicin. This form of tuberculosis is called multi-drug-resistant tuberculosis (MDR-TB) is rapidly on the rise globally.
Where are the rpoB mutations found in E coli?
Initial studies were done by Jin and Gross to generate rpoB mutations in E. coli that conferred resistance to rifampicin. Three clusters of mutations were identified, cluster I at codons 507-533, cluster II at codons 563-572, and cluster III at codon 687.