A First Insight into the katG and rpoB Gene Mutations of Multidrug-Resistant Mycobacterium tuberculosis Strains from Ecuador.
Microb Drug Resist
; 25(4): 524-527, 2019 May.
Article
em En
| MEDLINE
| ID: mdl-30513056
ABSTRACT
The aim of this study was to characterize the most frequent mutations associated with rifampicin (RIF) and isoniazid (INH) resistance of Mycobacterium tuberculosis isolates from Ecuador. Sequence analysis of 40 strains, resistant for the tuberculosis drugs INH, RIF, or for both showed that of the 31 strains with resistance to INH, 20 strains (64.5%) carried a mutation in the katG gene (codon 315). Eight INH-resistant strains carried a mutation in the katG gene at codon 463. This katG463 mutation, considered a phylogenetic marker, was exclusively found in INH-resistant strains and not in 121 INH-susceptible strains. Of the 35 strains resistant to RIF, 33 (93.9%) had mutations in the hot spot region of the rpoB gene, predominantly in codons 531, 516, and 526. Our results show that sequence-based detection for drug resistance of the katG will identify, respectively, 64.5% or, considering katG463 as a marker, 90.3% of the INH-resistant strains. Sequencing of the hot spot region of the rpoB gene will detect 94.3% of the RIF drug-resistant isolates in Ecuador. This is appropriate for fast screening for drug resistance with the GeneXpert MTB/RIF assay or by direct sequencing of a part of the genes katG and rpoB of PCR products obtained from DNA isolation from primary cultures.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Tuberculose Resistente a Múltiplos Medicamentos
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Farmacorresistência Bacteriana
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Mutação
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Mycobacterium tuberculosis
Limite:
Humans
País/Região como assunto:
America do sul
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Ecuador
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article