Department of Clinical Laboratory Medicine, Medical College of Taizhou University Affiliated Taizhou Municipal Hospital, 381 East Road of Zhongshan of Jiaojiang District in Taizhou, Taizhou 318000, Zhejiang Province, PRC.
Department of Urology Surgery, Medical College of Taizhou University Affiliated Taizhou Municipal Hospital, Taizhou, Zhejiang Province, PRC.
J Microbiol Immunol Infect. 2015 Jun;48(3):284-90. doi: 10.1016/j.jmii.2014.01.007. Epub 2014 Mar 24.
BACKGROUND/PURPOSE: To investigate the characterization of bla(OxA-23) gene regions in isolates of Acinetobacter baumannii from Taizhou Municipal Hospital.
Fifty-nine non-repetitive, multiresistant (including imipenem-resistant) isolates of A. baumannii were recovered from clinical infections in hospitalized patients from January 2010 to August 2011 in Taizhou Municipal Hospital (affiliated with Taizhou University) in China. These isolates were genotyped using pulsed-field gel electrophoresis (PFGE). bla(OxA-23) β-lactamase and associated genetic structures were analyzed using polymerase chain reaction (PCR), and recombination plasmids were analyzed by BamHI- or SacI- restriction enzyme digestion; predicted promoter structures of bla(OxA-23) genes were determined and compared using protein-protein BLAST analysis.
Fifteen out of 59 isolates expressing imipenem-resistant A. baumannii clinical isolates acquired either a bla(OxA-23) β-lactamase gene. A new gene cluster (ISAba1-bla(OxA-23)-AMP) with three previously identified transposons (Tn2006, Tn2007, and Tn2008) and one previously identified gene cluster (ISAba1- bla(OxA-23)) was found in the isolates. Recombination plasmids were analyzed by restriction enzyme digestion.
Our results indicate that pattern A was the most prevalent molecular type based on PFGE, and that different clones might be widespread with a majority of ISAba1-bla(OxA-23) clonal lineages in the 15 PCR positive isolates of A. baumannii in the hospital.
背景/目的：研究泰州医院鲍曼不动杆菌分离株 bla(OxA-23) 基因区域的特征。
从 2010 年 1 月至 2011 年 8 月期间，中国泰州大学附属泰州医院住院患者的临床感染中，回收了 59 株非重复、多药耐药（包括耐亚胺培南）的鲍曼不动杆菌分离株。这些分离株通过脉冲场凝胶电泳（PFGE）进行基因分型。使用聚合酶链反应（PCR）分析 bla(OxA-23) β-内酰胺酶和相关遗传结构，并通过 BamHI 或 SacI 限制性内切酶消化分析重组质粒；使用蛋白-蛋白 BLAST 分析确定和比较 bla(OxA-23) 基因的预测启动子结构。
在 59 株表达耐亚胺培南的鲍曼不动杆菌临床分离株中，有 15 株获得了 bla(OxA-23) β-内酰胺酶基因。在分离株中发现了一个新的基因簇（ISAba1-bla(OxA-23)-AMP），其中包含三个先前鉴定的转座子（Tn2006、Tn2007 和 Tn2008）和一个先前鉴定的基因簇（ISAba1-bla(OxA-23)）。通过限制性内切酶消化分析重组质粒。
我们的结果表明，基于 PFGE，模式 A 是最常见的分子类型，并且不同的克隆可能广泛存在，在医院的 15 株 bla(OxA-23) PCR 阳性鲍曼不动杆菌分离株中，大多数为 ISAba1-bla(OxA-23) 克隆谱系。
