First report of an Escherichia coli strain from swine carrying an OXA-181 carbapenemase and the colistin resistance determinant MCR-1
First report of an Escherichia coli strain from swine carrying an OXA-181 carbapenemase and the colistin resistance determinant MCR-1
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DOI：
10.1016/j.ijantimicag.2017.03.014
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发表时间：
2017-08-01
影响因子：
10.8
通讯作者：
Ewers, Christa
中科院分区：
文献类型：
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作者：
Pulss, Sandra;Semmler, Torsten;Ewers, Christa
肠杆菌科中质粒介导的碳青霉烯类和粘菌素耐药性代表了一种新出现的公共卫生威胁。尽管动物已被确定为多重耐药（MDR）细菌的相关来源，但只有少数报告表明动物分离株中存在碳青霉烯酶。在这项研究中，从2160头猪中获得的7850株粪便大肠杆菌分离株使用补充美罗培南的Mueller-Hinton琼脂筛选碳青霉烯类抗生素的不敏感性。11株分离株在含美罗培南的琼脂上生长，但只有2株经PCR证实为碳青霉烯酶基因阳性，即bla（OXA-48样）。这两种分离株来自意大利同一农场饲养的不同猪，通过多位点序列分型（MLST）（包括ST 359和ST 641），两种分离株在遗传上不相关。全基因组测序显示两株分离株均存在bla（OXA-181）;此外，在一株分离株中发现了粘菌素耐药基因mcr-1和氨基糖苷类耐药基因阿尔马。bla（OXA-181）抗性基因位于复制子类型IncX 3的51.5-kb非接合质粒上，mcr-1基因位于33.3-kb可转移IncX 4质粒上。质粒pEcIHIT 31346-OXA-181和pEcIHIT 31346-MCR-1与已发表的来自各种人和动物来源的质粒的高度核苷酸相似性（>99%）表明，特异性抗生素耐药质粒在大肠杆菌中循环。大肠杆菌菌株和脊椎动物物种的障碍。尽管碳青霉烯类抗生素还未被批准用于家畜，但猪大肠杆菌中碳青霉烯酶的总体流行率仍高于其他抗生素。大肠杆菌的耐药性似乎很低，但目前的研究结果表明，即使是猪也可以携带耐药菌株，这些菌株对几种最后一线抗生素具有累积的质粒介导的耐药性。(C)2017 Elsevier B. V.和国际化疗学会。All rights reserved.
Plasmid-mediated resistance to carbapenems and colistin in Enterobacteriaceae represents an emerging public health threat. Although animals have been identified as a relevant source of multidrug-resistant (MDR) bacteria, there are only a few reports on the presence of carbapenemases in animal isolates. In this study, 7850 faecal Escherichia coli isolates obtained from 2160 pigs were screened for carbapenem non-susceptibility using Mueller-Hinton agar supplemented with meropenem. Eleven isolates showed growth on meropenem-containing agar but only two proved positive by PCR for a carbapenemase gene, namely bla(OXA-48-like). The two isolates were obtained from different pigs housed at the same farm in Italy and were not genetically related by multilocus sequence typing (MLST), comprising ST359 and ST641. Whole-genome sequencing revealed the presence of bla(OXA-181) in both isolates; in addition, the colistin resistance gene mcr-1 and aminoglycoside resistance gene armA were found in one isolate. The bla(OXA-181) resistance gene was located on a 51.5-kb non-conjugative plasmid of replicon type IncX3 and the mcr-1 gene on a 33.3-kb transferable IncX4 plasmid. The high nucleotide similarity (>99%) of plasmids pEcIHIT31346-OXA-181 and pEcIHIT31346-MCR-1 to published plasmids from various human and animal sources suggests that specific antibiotic resistance plasmids are circulating among E. coli strains worldwide and across vertebrate species barriers. Although carbapenems are not licensed for use in livestock and the overall prevalence of carbapenemases in porcine E. coli appears to be low, the current findings indicate that even pigs can host MDR strains with accumulated plasmid-mediated resistance against several last-line antibiotics. (C) 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.