High Rate of Serotype Switching and Genetic Variations Indicates Widespread Recombination Between Clinical and Commensal Penicillin-Nonsusceptible Streptococcus pneumoniae in Tehran.
Microb Drug Resist
; 25(6): 865-873, 2019.
Article
em En
| MEDLINE
| ID: mdl-30785836
ABSTRACT
A total of 161 Streptococcus pneumoniae were collected between 2013 and 2015 in Tehran, Iran. The strains were tested for antimicrobial susceptibility and minimum inhibitory concentrations, serotyped, and genotyped by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Penicillin-binding proteins (PBPs) were also typed by restriction fragment length polymorphism (PBP-RFLP). Out of 161 strains, 32 isolates (20%) were highly resistant to penicillin. The most frequent serotypes among the penicillin-nonsusceptible S. pneumoniae (PNSP) were 14 (24%), 23F (18%), and 19F (17%). RFLP of pbp2b, pbp2x, and pbp1a genes revealed 8, 6, and 7 different patterns, respectively. Analysis of 93 PNSP isolates displayed 80 PFGE types with 8 common types constituting 21 (23%) isolates. The remaining 72 isolates (77%) were single types. MLST indicated a high degree of genetic diversity among the 93 PNSP with 36 different sequence types. Six internationally known penicillin resistant clones were identified in our isolates among which Spain23F-1 (ST81), Spain6B-2 (ST90), and Spain9V-3 (ST156) were the predominant clones. The results indicated international identifiable clones of S. pneumoniae, especially Spain23F-1 with high penicillin resistance could play a major role in spread of antimicrobial resistance in Iran. The extensive sequence variation in PBP2x, PBP2b, and PBP1a in resistant strains of clinical and commensal S. pneumoniae was suggestive of a widespread homologous recombination within S. pneumoniae populations.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Penicilinas
/
Streptococcus pneumoniae
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Proteínas de Bactérias
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Polimorfismo de Fragmento de Restrição
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Resistência às Penicilinas
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Proteínas de Ligação às Penicilinas
Limite:
Humans
País/Região como assunto:
Asia
Idioma:
En
Revista:
Microb Drug Resist
Assunto da revista:
MICROBIOLOGIA
/
TERAPIA POR MEDICAMENTOS
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Irã