Co-location of the oxazolidinone resistance genes optrA and cfr on a multiresistance plasmid from Staphylococcus sciuri
Co-location of the oxazolidinone resistance genes optrA and cfr on a multiresistance plasmid from Staphylococcus sciuri
复制标题
恶唑烷酮抗性基因 optrA 和 cfr 在松鼠葡萄球菌多重抗性质粒上的共定位
DOI：
10.1093/jac/dkw040
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发表时间：
2016-06-01
影响因子：
5.2
通讯作者：
Shen, Jianzhong
中科院分区：
文献类型：
--
作者：
Li, Dexi;Wang, Yang;Shen, Jianzhong
目的：目的：检测和鉴定葡萄球菌中恶唑烷酮/苯甲酚耐药基因optrA，方法：采用PCR方法对50株氟苯尼考MIC>= 16 mg/L的猪葡萄球菌进行optrA基因的筛选。optrA的可转移性通过转化和缀合来检查。该基因的功能通过在易感葡萄球菌宿主中克隆和表达来证实。结果：1株松鼠葡萄球菌optrA基因阳性。该菌株在60563 bp的多抗性质粒pWo 28 -3上携带optrA基因，同时还携带cfr、fexA、aadD、ble和aacA-aphD等抗性基因。质粒pWo 28 -3由三个区域（A、B和C）组成。A区含有除optrA外的所有抗性基因，与来自Jeotgalicoccus pinnipedialis和Staphylococcus lentus的质粒pJP 1和pJP 1-like的相应区域的核苷酸序列同源性分别>= 99.8%。位于区域B的optrA基因与粪肠球菌质粒pE 349的optrA基因的不同之处在于四个核苷酸取代，这也导致氨基酸取代。该optrA变体还赋予葡萄球菌对恶唑烷酮类和酚类的耐药性。C区的28个基因代表质粒骨架，显然是从葡萄球菌、肠球菌和诺氏球菌中获得的。结论：这是首次报道葡萄球菌中的optrA基因以及optrA和cfr在同一质粒上的共存。该质粒的传播将实质上限制恶唑烷酮的功效。对人和动物源性葡萄球菌中optrA的监测是迫切需要的。
Objectives: To identify and characterize the oxazolidinone/phenicol resistance gene optrA in Staphylococcus isolates.Methods: Fifty porcine staphylococci with florfenicol MICs of >= 16 mg/L were screened by PCR for the presence of the optrA gene. Transferability of optrA was examined by transformation and conjugation. Functionality of this gene was confirmed by cloning and expression in a susceptible Staphylococcus host. The optrA-carrying plasmid was completely sequenced and analysed.Results: A single Staphylococcus sciuri was optrA positive. This isolate carried the optrA gene on the 60563 bp multiresistance plasmid pWo28-3, which also harboured the resistance genes, cfr, fexA, aadD, ble and aacA-aphD. Plasmid pWo28-3 is composed of three regions (A, B and C). Region A, which harboured all resistance genes except optrA, showed >= 99.8% nucleotide sequence identity to the corresponding region of plasmids pJP1 and pJP1-like from Jeotgalicoccus pinnipedialis and Staphylococcus lentus, respectively. The optrA gene located in region B differed from the optrA gene of the Enterococcus faecalis plasmid pE349 by four nucleotide substitutions, which also resulted in amino acid substitutions. This optrA variant also conferred resistance to oxazolidinones and phenicols in staphylococci. The 28 genes in region C represent the plasmid backbone and were apparently acquired from staphylococci, enterococci and nosocomiicocci.Conclusions: This is the first report of the optrA gene in staphylococci and of the coexistence of optrA and cfr on the same plasmid. Dissemination of this plasmid will substantially limit the efficacy of oxazolidinones. Surveillance of optrA in staphylococci of both human and animal origin is urgently warranted.