RESUMEN
Denaturing high-performance liquid chromatography (DHPLC) is a relatively new technique, which utilizes heteroduplex formation between wild-type and mutated DNA strands to identify point mutations. Heteroduplex molecules are separated from homoduplex molecules by ion-pair, reverse-phase liquid chromatography on a special column matrix with partial heat denaturation of the DNA strands. In order to investigate the application of this method for point mutation detection in drug-resistant genes of Mycobacterium tuberculosis, katG, rpoB, embB, gyrA, pncA and rpsL genes, which are responsible for isoniazid, rifampicin, ethambutol, fluoroquinolone, pyrazinamide and streptomycin resistance, respectively, were detected by temperature-mediated DHPLC in 10 multidrug-resistant and 10 drug-susceptible clinical isolates. The DHPLC data were compared with those from a conventional MIC test. The results show that DHPLC is cost-effective with high capacity and accuracy, and is potentially useful for genotypic screening for mutations associated with anti-tuberculosis drug resistance.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Desoxirribonucleasas/metabolismo , Farmacorresistencia Bacteriana/genética , Mutación/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Ácidos Nucleicos Heterodúplex , Antituberculosos/farmacología , ADN Bacteriano , Desnaturalización de Ácido Nucleico , TemperaturaRESUMEN
Seventy-four Mycobacterium tuberculosis clinical isolates from China were subjected to drug susceptibility testing using ethambutol, isoniazid, rifampin, and ofloxacin. The results revealed that the presence of embB mutations did not correlate with ethambutol resistance but was associated with multiple-drug resistance, especially resistance to both ethambutol and rifampin.
Asunto(s)
Etambutol/farmacología , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Antituberculosos/farmacología , Proteínas Bacterianas/genética , China , Farmacorresistencia Bacteriana/genética , Humanos , Isoniazida/farmacología , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/aislamiento & purificación , Ofloxacino/farmacología , Pentosiltransferasa/genética , Rifampin/farmacología , Tuberculosis/microbiologíaRESUMEN
The antimycobacterial activity of "Hikari-Gintech" powder, which has photocatalytic activity, was examined in vitro. Both powder dissolved in liquid and Hikari-Gintech-coated cloths showed strong antimycobacterial activity against Mycobacterium tuberculosis H37Rv, M. bovis BCG Pasteur, multi-drug-resistant M. tuberculosis (a clinical isolate) and M. avium. Hikari-Gintech powder appeared to affect mycobacterial cell wall metabolism rather than mycobacterial DNA because no damage to mycobacterial DNA was detected after spraying with Hikari-Gintech solution.