Molecular characterization of methicillin-resistant Staphylococcus epidermidis strains from bacteraemic patients
Molecular characterization of methicillin-resistant Staphylococcus epidermidis strains from bacteraemic patients
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DOI：
10.1111/j.1469-0691.2008.02080.x
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发表时间：
2008-11-01
影响因子：
14.2
通讯作者：
Vuopio-Varkila, J.
中科院分区：
文献类型：
--
作者：
Ibrahem, S.;Salmenlinna, S.;Vuopio-Varkila, J.
为了研究临床耐甲氧西林表皮葡萄球菌（MRSE）菌株及其葡萄球菌盒式染色体mec（SCCmec）元件的克隆性，选择了芬兰赫尔辛基大学医院三个单位菌血症患者的60株MRSE分离株，涵盖1990-1993年和1997-1998年期间。通过脉冲场凝胶电泳 (PFGE)、多位点序列分型和 SCCmec 分型对 MRSE 菌株进行分析。鉴定出 11 种具有序列类型 ST2（克隆复合体 2；CC2）的 PFGE 类型 (FIN-SE-1-11)。应用先前建立的耐甲氧西林金黄色葡萄球菌 SCCmec 标准来命名 MRSE SCCmec 复合物，发现 7% 的分离株携带 SCCmec IA 型（ccrA1，B 类），而大多数 (93%) 产生六种不可分型的 SCCmec PCR 模式 (P1-P6)。在每个 SCCmec PCR 模式中，检测到两个 ccr 重组酶基因（ccrA2 和 ccrA3）和两个 mec 基因复合物（A 类和 B 类）。此外，ccrC 基因与六种模式中的三种相关。总之，MRSE 菌株在遗传上彼此相关 (ST2)，但它们的 SCCmec 复合物是先前在 SCCmec III 型和 IV 型中识别的元素的独特组合。
In order to study the clonality of clinical methicillin-resistant Staphylococcus epidermidis (MRSE) strains and their staphylococcal cassette chromosome mec (SCCmec) elements, 60 isolates of MRSE from bacteraemic patients in three units of the Helsinki University Hospital, Finland were selected, covering the periods 1990-1993 and 1997-1998. The MRSE strains were analysed by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing and SCCmec typing. Eleven PFGE types (FIN-SE-1-11) with sequence type ST2 (clonal complex 2; CC2) were identified. The previously established methicillin-resistant Staphylococcus aureus SCCmec criteria were applied to name the MRSE SCCmec complexes, and it was found that 7% of the isolates carried SCCmec type IA (ccrA1, class B), whereas the majority (93%) yielded six non-typeable SCCmec PCR patterns (P1-P6). Within each SCCmec PCR pattern, two ccr recombinase genes (ccrA2 and ccrA3) and two mec gene complexes (class A and class B) were detected. In addition, the ccrC gene was associated with three of the six patterns. In conclusion, the MRSE strains were genetically related to each other (ST2) but their SCCmec complexes were unique combinations of elements previously recognized among SCCmec types III and IV.