First detection of mobilized colistin resistance mcr-1 gene in Escherichia coli isolated from livestock and sewage in Iran

New Microbes and New Infections

卷:41

S. Robatjazi¹  G.H. Shahbazi²  F. Nikkhahi³  M. Niazadeh³  S.M.Amin Marashi³  A. Javadi³  N. Emam³  P. Aris³ 

[1] Corresponding author: F. Nikkhahi, Medical Microbiology Research Center, Qazvin University of Medical Sciences, PO Box 34199, 15315, Qazvin, Iran.;

[2] Department of Biostatics, Qazvin University of Medical Sciences, Qazvin, Iran;

[3] Medical Microbiology Research Center, Iran;

关键词: Colistin resistance;    Escherichia coli;    livestock;    mcr-1;   

DOI  :  

来源: DOAJ

【 摘 要 】

Currently, few studies have investigated the mechanisms of resistance to colistin in Iran. The aim of this study was to investigate mcr-harbouring Escherichia coli dissemination in livestock and sewage in Iran. A total of 115 samples from cows (n = 38), chickens (n = 47) and urban sewage samples (n = 30) were collected. The presence of genes including mcr1–6 and ampC β-lactamase (blaMOX, blaCIT, blaDHA, blaACC, blaEBC, blaFOX) for colistin-resistant isolates was investigated by multiplex PCR method. Genetic association of colistin-resistant strains was also evaluated by ERIC PCR. Sixty-five isolates were identified as E. coli. Meaningless were resistant to colistin. The highest (26.1%) and lowest (3.07%) resistance were shown to ampicillin and meropenem respectively. Among the three colistin-resistant isolates, 2 (66%) were multidrug resistant, with one of them being mcr-1 positive and the other one positive for DHA ampC β-lactamase gene. No mcr2–6 genes were found. Minimum inhibitory concentration of mcr-producing isolate was 4 mg/L by microbroth dilution. This study reports, first the detection of mcr-1 in E. coli from farm animals in Iran, a finding that is indicative of a global distribution of this plasmidic element and threatning the use of colistin as a last resort antibiotic. No clonal relationship was observed between the colistin-resistant E. coli isolates by ERIC-PCR. Monitoring the presence of these strains in animal sources help as to controlling the spread of resistance genes from animal to human is vital.

【 授权许可】

Unknown