Co-existence of two plasmids harboring transferable resistance-nodulation-division pump gene cluster, tmexCD1-toprJ1, and colistin resistance gene mcr-8 in Klebsiella pneumoniae.
Ann Clin Microbiol Antimicrob
; 23(1): 67, 2024 Jul 26.
Article
en En
| MEDLINE
| ID: mdl-39061085
ABSTRACT
BACKGROUND:
The emergence of plasmid-mediated mobile colistin resistance (mcr) gene poses a great challenge to the clinical application of polymyxins. To date, mcr-1 to mcr-10 have been found in animals, humans, and the environment. Among them, mcr-8 was first identified in Klebsiella pneumoniae (K. pneumoniae) of swine origin, and then mcr-8.1 to mcr-8.5 were successively identified. Notably, K. pneumoniae is the major host of the mcr-8 gene in both animals and humans. This study aims to explore the characteristics of K. pneumoniae strains carrying the mcr-8 gene and tmexCD1-toprJ1 gene cluster and investigate the correlation between these two antibiotic resistance genes.METHODS:
The isolates from the poultry farms and the surrounding villages were identified by mass spectrometer, and the strains positive for mcr-1 to mcr-10 were screened by polymerase chain reaction (PCR). The size of the plasmid and the antimicrobial resistance genes carried were confirmed by S1-nuclease pulsed-field gel electrophoresis (S1-PFGE) and Southern hybridization, and the transferability of the plasmid was verified by conjugation experiments. Antimicrobial susceptibility testing (AST) and whole genome sequencing (WGS) were used to characterize the strains.RESULTS:
Two K. pneumoniae isolates (KP26 and KP29) displaying polymyxin resistance were identified as mcr-8 gene carriers. Besides that, tigecycline-resistant gene cluster tmexCD1-toprJ1 was also found on the other plasmid which conferred strain resistance to tigecycline. Through epidemiological analysis, we found that the mcr-8 gene has dispersed globally, circulating in the human, animals, and the environment. Furthermore, our analysis suggests that the coexistence of mcr-8 and tmexCD1-toprJ1 on a single plasmid might evolved through plasmid recombination.CONCLUSIONS:
Although the mcr-8 and tmexCD1-toprJ1 gene clusters in the two strains of K. pneumoniae in this study were on two different plasmids, they still pose a potential threat to public health, requiring close monitoring and further study.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Plásmidos
/
Infecciones por Klebsiella
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Pruebas de Sensibilidad Microbiana
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Familia de Multigenes
/
Colistina
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Farmacorresistencia Bacteriana
/
Klebsiella pneumoniae
/
Antibacterianos
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Ann Clin Microbiol Antimicrob
Asunto de la revista:
MICROBIOLOGIA
/
TERAPIA POR MEDICAMENTOS
Año:
2024
Tipo del documento:
Article
País de afiliación:
China