Molecular Characteristics of ST1193 Clone among Phylogenetic Group B2 Non-ST131 Fluoroquinolone-Resistant Escherichia coli.
Molecular Characteristics of ST1193 Clone among Phylogenetic Group B2 Non-ST131 Fluoroquinolone-Resistant Escherichia coli.
复制标题
系统发育群B2非ST131氟喹诺酮类耐药大肠杆菌中ST1193克隆的分子特征
DOI：
10.3389/fmicb.2017.02294
复制
发表时间：
2017
影响因子：
5.2
通讯作者：
Li B
中科院分区：
文献类型：
--
作者：
Wu J;Lan F;Lu Y;He Q;Li B
目的：序列类型 1193 是氟喹诺酮耐药大肠杆菌 (FQr E. coli) 中一个新的、有毒的、耐药谱系。在这项研究中，我们调查了从中国大学医院分离出的这种克隆的流行率和分子特征。方法：收集2014年8月至2015年8月在中国某大学附属医院收集的73株系统发育群B2-FQr-non-ST131分离株。通过多位点序列分型筛选分离株中的 ST1193。然后对大肠杆菌 ST1193 进行乳糖发酵测定、药敏测试、毒力基因分型、基于 PCR 的 O 型、脉冲场凝胶电泳 (PFGE) 和 FQr 机制分析。结果：73 株 B2-FQr-non ST131 大肠杆菌分离株中，69.9% (n = 51) 为 ST1193。 90.2% (46/51) 的 ST1193 分离株为 O75 血清型，96.1% (49/51) 的 ST1193 分离株为乳糖非发酵菌。 PFGE 鉴定出 35 个簇。 ST1193 分离株表现出一组 3 个保守突变，定义了喹诺酮抗性决定区替换（gyrA S83L、D87N 和 parC S80I）。在这些大肠杆菌 ST1193 分离株中检测到的最常见的 VF 基因是 fyuA（耶尔森菌素，96.1%）、fimH（1 型菌毛，94.1%）、iutA（铁摄取基因，90.2%）、kpsMT II（II 组胶囊，90.2%）、kpsK1（K1 胶囊，86.3%）和 PAI。结论：ST1193 谱系占 B2-FQr-非 ST131 组大肠杆菌临床分离株的大部分。大多数 ST1193 血清型为 O75，乳糖非发酵型。未来需要针对这种新出现的大肠杆菌克隆：B2-FQr-ST1193 制定战略监测和控制方案。
Objectives: Sequence type 1193 is emerging as a new, virulent and resistant lineage among fluoroquinolone resistant Escherichia coli (FQr E. coli). In this study, we investigated the prevalence and molecular characteristics of this clone isolated from a Chinese university hospital. Methods: 73 phylogenetic group B2-FQr-non-ST131 isolates were collected from August 2014 and August 2015 at a Chinese university hospital. Isolates were screened for ST1193 by multilocus sequence typing. E. coli ST1193 then underwent lactose fermentation determination, susceptibility testing, virulence genotyping, PCR-based O typing, pulsed-field gel electrophoresis (PFGE) and FQr mechanism analysis. Results: Of 73 B2-FQr-non ST131 E. coli isolates, 69.9% (n = 51) were ST1193. 90.2% (46/51) of ST1193 isolates were O75 serotype and 96.1% (49/51) of the ST1193 isolates were lactose non-fermenters. 35 clusters were identified by PFGE. ST1193 isolates exhibited a set of 3 conserved mutations defining quinolone-resistance determining region substitutions (gyrA S83L, D87N, and parC S80I). The most frequent VF genes detected in these E. coli ST1193 isolates were fyuA (yersiniabactin, 96.1%), fimH (type 1 fimbriae, 94.1%), iutA (iron uptake gene, 90.2%), kpsMT II (group II capsule, 90.2%), kpsK1 (K1 capsule, 86.3%) and PAI. Conclusion: ST1193 lineage accounts for the majority of group B2-FQr-non-ST131 E. coli clinical isolates. Most of the ST1193 are serotype O75 and lactose non-fermenting. Strategic surveillance and control schemes are needed in the future for this newly emerging clone of E. coli: B2-FQr-ST1193.