Relationship between pyrazinamide resistance, loss of pyrazinamidase activity, and mutations in the pncA locus in multidrug-resistant clinical isolates of Mycobacterium tuberculosis.
نویسندگان
چکیده
Sixty-two Mycobacterium tuberculosis isolates were tested for pyrazinamidase activity, and their pyrazinamide susceptibility was determined by the radiometric method. Sequencing of pncA genes in the 23 resistant strains revealed mutations in 16 pyrazinamidase-negative strains, 11 of which had not been previously described. Six isolates containing wild-type pncA might possess alternative resistance mechanisms.
منابع مشابه
pncA mutations in pyrazinamide-resistant Mycobacterium tuberculosis isolates in Portugal.
The nucleotide sequences of the pncA genes within 55 multidrug-resistant pyrazinamide-resistant Mycobacterium tuberculosis clinical isolates were determined. Fifty-three out of the 55 isolates were pyrazinamidase (PZase) negative. Four strains contained a wild-type pncA gene, and PZase activity was undetectable in two of these strains. Seven of the 18 identified pncA mutations found have not be...
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عنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 43 9 شماره
صفحات -
تاریخ انتشار 1999