A GC1 Acinetobacter baumannii isolate carrying AbaR3 and the aminoglycoside resistance transposon TnaphA6 in a conjugative plasmid.
J Antimicrob Chemother
; 69(4): 955-8, 2014 Apr.
Article
em En
| MEDLINE
| ID: mdl-24235096
ABSTRACT
OBJECTIVES:
To locate the acquired antibiotic resistance genes, including the amikacin resistance transposon TnaphA6, in the genome of an Australian isolate belonging to Acinetobacter baumannii global clone 1 (GC1).METHODS:
A multiply antibiotic-resistant GC1 isolate harbouring TnaphA6 was sequenced using Illumina HiSeq, and reads were used to generate a de novo assembly and determine multilocus sequence types (STs). PCR was used to assemble the AbaR chromosomal resistance island and a large plasmid carrying TnaphA6. Plasmid DNA sequences were compared with ones available in GenBank. Conjugation experiments were conducted.RESULTS:
The A. baumannii GC1 isolate G7 was shown to include the AbaR3 antibiotic resistance island. It also contains an 8.7 kb cryptic plasmid, pAb-G7-1, and a 70,100 bp plasmid, pAb-G7-2, carrying TnaphA6. pAb-G7-2 belongs to the Aci6 Acinetobacter plasmid family. It encodes transfer functions and was shown to conjugate. Plasmids related to pAb-G7-2 were detected in further amikacin-resistant GC1 isolates using PCR. From the genome sequence, isolate G7 was ST1 (Institut Pasteur scheme) and ST231 (Oxford scheme). Using Oxford scheme PCR-based methods, the isolate was ST109 and this difference was traced to a single base difference resulting from the inclusion of the original primers in the gpi segment analysed.CONCLUSIONS:
The multiply antibiotic-resistant GC1 isolate G7 carries most of its resistance genes in AbaR3 located in the chromosome. However, TnaphA6 is on a conjugative plasmid, pAb-G7-2. Primers developed to locate TnaphA6 in pAb-G7-2 will simplify the detection of plasmids related to pAb-G7-2 in A. baumannii isolates.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plasmídeos
/
Elementos de DNA Transponíveis
/
Farmacorresistência Bacteriana Múltipla
/
Acinetobacter baumannii
/
Aminoglicosídeos
/
Antibacterianos
Limite:
Humans
País/Região como assunto:
Oceania
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article