title: Mutations in the pncA and rpsA genes among 77 Mycobacterium tuberculosis isolates in Kazakhstan.
abstract: METHODS
  Pyrazinamide (PZA), an important first-line drug for anti-tuberculosis treatment, demonstrates potent activity against semi-dormant bacilli in acidic environments. However, the diagnosis of PZA resistance is often impeded by technical difficulties.
  
  
  OBJECTIVE
  To characterise mutations in the pncA and rpsA genes among PZA-resistant and PZA-susceptible clinical Mycobacterium tuberculosis isolates circulating in Kazakhstan. The potential use of genotyping to identify PZA resistance was also investigated.
  
  
  METHODS
  PZA drug susceptibility testing and pncA and rpsA gene sequencing were performed on 77 clinical M. tuberculosis isolates; mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing was performed on 74 clinical M. tuberculosis isolates.
  
  
  RESULTS
  Of the 77 clinical M. tuberculosis isolates, 41 (53.2%) were phenotypically resistant to PZA, whereas 36 (46.7%) were susceptible; 48 (62.3%) of these isolates were also multidrug-resistant (MDR). Furthermore, 38 (49.3%) clinical isolates showed mutations in the pncA gene and its flanking region; the majority of these isolates (n = 36, 94.7%) were also MDR. Gene sequencing showed that only synonymous substitutions affecting rpsA occurred. MIRU-VNTR typing revealed that 78.4% of isolates were of the Beijing genotype.
  
  
  CONCLUSIONS
  Sequencing revealed that mutations in pncA, but not in rpsA, occurred in PZA-resistant M. tuberculosis isolates circulating in the territory of Kazakhstan.
authors.affiliation: National Center for Biotechnology of the Republic of Kazakhstan, Astana, Kazakhstan.
authors.forename: A
authors.initials: A
authors.lastname: Akhmetova
authors.affiliation: National Center for Biotechnology of the Republic of Kazakhstan, Astana, Kazakhstan.
authors.forename: U
authors.initials: U
authors.lastname: Kozhamkulov
authors.affiliation: National Centre for Tuberculosis Problems of the Republic of Kazakhstan, Almaty, Kazakhstan.
authors.forename: V
authors.initials: V
authors.lastname: Bismilda
authors.affiliation: National Centre for Tuberculosis Problems of the Republic of Kazakhstan, Almaty, Kazakhstan;
authors.forename: L
authors.initials: L
authors.lastname: Chingissova
authors.affiliation: National Centre for Tuberculosis Problems of the Republic of Kazakhstan, Almaty, Kazakhstan.
authors.forename: T
authors.initials: T
authors.lastname: Abildaev
authors.affiliation: Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russian Federation; Novosibirsk State University, Novosibirsk, Russian Federation.
authors.forename: M
authors.initials: M
authors.lastname: Dymova
authors.affiliation: Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russian Federation; Novosibirsk State University, Novosibirsk, Russian Federation.
authors.forename: M
authors.initials: M
authors.lastname: Filipenko
authors.affiliation: National Center for Biotechnology of the Republic of Kazakhstan, Astana, Kazakhstan.
authors.forename: E
authors.initials: E
authors.lastname: Ramanculov
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000581:Amidohydrolases / Q000235:genetics*; D000995:Antitubercular Agents / Q000494:pharmacology*; D002648:Child; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D007623:Kazakhstan; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D018598:Minisatellite Repeats; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D011718:Pyrazinamide / Q000494:pharmacology*; D012269:Ribosomal Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000379:methods; D014376:Tuberculosis / Q000188:drug therapy / Q000382:microbiology; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D004269:DNA, Bacterial; D012269:Ribosomal Proteins; D011718:Pyrazinamide; D000581:Amidohydrolases; C487496:PncA protein, Mycobacterium tuberculosis