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Mycobacterium tuberculosis resistance to rifampicin is mainly mediated through mutations in the rpoB gene. The effects of rpoB mutations are relieved by secondary mutations in rpoA or rpoC genes. This study aims to identify mutations in rpoB, rpoA, and rpoC genes of Mycobacterium tuberculosis isolates and clarify their contribution to rifampicin re...
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Context 1
... primer sets were designed for target genes (rpoB, rpoA and rpoC) as described in (Table 1) by NCBI primer designing tool (https://www.ncbi.nlm.nih.gov/tools/primer-blast/) and Clone Manager software was used for checking primers specificity. Target genes of M. tuberculosis were amplified by PCR using TC-412 thermal cycler (Techne-Japan) and amplicon sizes confirmed. ...Context 2
... [DNA Sequence data] used to support the findings of this study have been deposited in the [GenBank] under the following accession numbers: MK874753-MK874779, and MK887216-MK887231. none none none none M479L ATG > TTG S531L TCG > TTG 15 15 none none none none M479L ATG > TTG S531L TCG > TTG 16 16 none none T187A T332S ACC > GCC ACC> AGC L943P CTG > CCG none none 17 ...Citations
... Rifampicin (RIF) ( fig. 1c) is a semi-synthetic antibiotic derived from rifamycin SV and chemically is (2S,12Z,14E,16S,17S,18R,19R,20R ,21S,2R,23S,24E)-5,6,9.,17,19-pentahydroxy-23methoxy-2,4,12,16,18,20,22-heptamethyl-8-[[(4methylpiperazin-1-yl) imino] methyl]-1,11 -dioxo-1,2dihydro-2,7-(epoxypentadeca [1,11,13] trieneimino) naphtho[2,1-b] furan-21-yl acetate [6] active in vitro against microbacteria and gram-positive microorganisms. Since its development, it has been used in veterinary and human medicine to treat tuberculosis and other mycobacterial infections [9][10][11]. ...
... 1c) is a semi-synthetic antibiotic derived from rifamycin SV and chemically is (2S,12Z,14E,16S,17S,18R,19R,20R ,21S,2R,23S,24E)-5,6,9.,17,19-pentahydroxy-23methoxy-2,4,12,16,18,20,22-heptamethyl-8-[[(4methylpiperazin-1-yl) imino] methyl]-1,11 -dioxo-1,2dihydro-2,7-(epoxypentadeca [1,11,13] trieneimino) naphtho[2,1-b] furan-21-yl acetate [6] active in vitro against microbacteria and gram-positive microorganisms. Since its development, it has been used in veterinary and human medicine to treat tuberculosis and other mycobacterial infections [9][10][11]. ...
This study's objective is to assess how well UV spectrophotometry can be used in conjunction with multivariate calibration based on partial least squares (PLS) regression for concurrent quantitative analysis of antibacterial mixture (Levofloxacin (LIV), Metronidazole (MET), Rifampicin (RIF) and Sulfamethoxazole (SUL)) in their artificial mixtures and pharmaceutical formulations. The experimental calibration and validation matrixes were created using 42 and 39 samples, respectively. The concentration range taken into account was 0-17 μg/mL for all components. The calibration standards' absorbance measurements were made between 210 and 350 nm, with intervals of 0.2 nm. The associated parameters were examined in order to develop the optimal calibration model. The cross-validation method was used to determine the ideal number of components. The coefficient of determination (R2) and the root mean square error of calibration (RMSEC) are used to evaluate the calibration model. The relation between the LEV, MET, RIF, and SUL actual values and predicted values had a coefficient of determination that was higher than 0.997, showing very good accuracy of the devised approach. The obtained RMSEC values, 0.181056465 (LEV), 0.180375418 (MET), 0.142767171 (RIF), and 0.17157454 (SUL), show an analytical procedure with adequate precision. The suggested technique for quantitative analysis of the quaternary mixture of LEV, MET, RIF, and SUL have been applied successfully in different pharmaceutical preparations. The UV spectrophotometry assisted with chemometric-PLS without prior treatment, be utilised to resolve multicomponent mixtures successfully.
... Mutations in specific positions of the coding sequences are known to affect the binding of drugs to RNAP, leading to drug resistance (Haunreiter et al., 2019). Mutations in rpoB burdened a fitness cost in the absence of antibiotics, while compensatory mutations in rpoC could restore the fitness of rifampin-resistant bacteria (Brandis et al., 2012;Comas et al., 2012;de Vos et al., 2013;Tawgozy and Qarasnji, 2020). The specific SNPs detected in rpoB (Asp342 → Gly) and rpoC (Ala787 → Val) have not been described so far. ...
The usage of quaternary ammonium compounds (QACs) as disinfectants has increased dramatically since the outbreak of COVID-19 pandemic, leading to potentially accelerated emergence of antibiotic resistance. Long-term exposure to subinhibitory level QACs can lead to multidrug resistance, but the contribution of mutagenesis to resistance evolution is obscure. In this study, we subcultured E. coli K-12 under subinhibitory (0.25× and 0.5× Minimum Inhibitory Concentration, MIC) or inhibitory (1× and 2 × MIC) concentrations of benzalkonium chloride (BAC, mono-chained) or didecyldimethylammonium chloride (DDAC, twin-chained) for 60 days. The sensitivity of QAC-adapted cells to five typical antibiotics decreased significantly, and in particular, the MIC of rifampicin increased by 85 times. E. coli adapted faster to BAC but developed 20–167% higher antibiotic resistance with 56% more mutations under DDAC exposure. The broader mutations induced by QACs, including negative regulators (acrR, marR, soxR, and crp), outer membrane proteins and transporters (mipA and sbmA), and RNA polymerase (rpoB and rpoC), potentially contributed to the high multi-drug resistance. After QACs stresses were removed, the phenotypic resistance induced by subinhibitory concentrations of QACs was reversible, whereas that induced by inhibitory concentrations of QACs was irreversible. The different patterns and molecular mechanism of antibiotic resistance induced by BAC and DDAC is informative to estimating the risks of broader QACs present at varied concentrations in the environment.
