Characterization of the complete sequences and stability of plasmids carrying the genes aac(6')-Ib-cr or qnrS in Shigella flexneri in the Hangzhou area of China.
World J Microbiol Biotechnol
; 34(6): 72, 2018 May 18.
Article
em En
| MEDLINE
| ID: mdl-29777316
ABSTRACT
The aim of this study was to explore the fluoroquinolone resistance mechanism of aac (6')-Ib-cr and qnrS gene by comparing complete sequences and stability of the aac(6')-Ib-cr- and qnrS-positive plasmids from Shigella isolates in the Hangzhou area of China. The complete sequences of four newly acquired plasmids carrying aac(6')-Ib-cr or qnrS were compared with those of two plasmids obtained previously and two similar reference Escherichia coli plasmids. The results showed that the length, antibiotic resistance genes and genetic environment were different among the plasmids. Moreover, the plasmid stability of three wild-type isolates and five plasmid transformants carrying aac(6')-Ib-cr and/or qnrS was measured in vitro, and all eight isolates were found to have lost their aac(6')-Ib-cr- or qnrS-positive plasmids to a different extent at different stages. When the plasmids were electroporated into Shigella flexneri or they lost positive plasmids, the MICs of ciprofloxacin increased or decreased two- to eightfold for aac(6')-Ib-cr-positive plasmids and 16- to 32-fold for qnrS-positive plasmids. To our knowledge, this is the first report comparing the complete sequences and describing stability for the aac(6')-Ib-cr- and qnrS-positive plasmids from Shigella isolates.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plasmídeos
/
Shigella flexneri
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Farmacorresistência Bacteriana Múltipla
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Genes Bacterianos
Limite:
Humans
País/Região como assunto:
Asia
Idioma:
En
Revista:
World J Microbiol Biotechnol
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
China