Giske Christian G, Libisch Balázs, Colinon Céline, Scoulica Effie, Pagani Laura, Füzi Miklós, Kronvall Göran, Rossolini Gian Maria
Department of Clinical Microbiology L2:02, Karolinska Institutet-MTC, Karolinska University Hospital Solna, SE-17176 Stockholm, Sweden.
J Clin Microbiol. 2006 Dec;44(12):4309-15. doi: 10.1128/JCM.00817-06. Epub 2006 Oct 4.
Ten multidrug-resistant Pseudomonas aeruginosa strains producing VIM-1-like acquired metallo-beta-lactamases (MBLs), isolated from four European countries (Greece, Hungary, Italy, and Sweden), were analyzed for genetic relatedness by several methodologies, including fliC sequence analysis, macrorestriction profiling of genomic DNA by pulsed-field gel electrophoresis (PFGE), random amplification of polymorphic DNA (RAPD), and multilocus sequence typing (MLST). The four approaches yielded consistent results overall but showed different resolution powers in establishing relatedness between isolates (PFGE>RAPD>MLST>fliC typing) and could usefully complement each other to address issues in the molecular epidemiology of P. aeruginosa strains producing acquired MBLs. In particular, the recently developed MLST approach was useful in revealing clonal relatedness between isolates when this was not readily apparent using RAPD and PFGE, and it suggested a common ancestry for some of the VIM-1-like MBL-positive P. aeruginosa strains currently spreading in Europe. The MBL producers belonged in three clonal complexes/burst groups (BGs). Of these, one corresponded to the previously described BG4 and included serotype O12 strains from Hungary and Sweden, while the other two were novel and included serotype O11 or nonserotypable strains from Greece, Sweden, and/or Italy. Comparison of the integrons carrying blaVIM-1-like cassettes of various isolates revealed a remarkable structural heterogeneity, suggesting the possibility that multiple independent events of acquisition of different blaVIM-containing integrons had occurred in members of the same clonal lineage, although a contribution of integrase-mediated cassette shuffling or other recombination mechanisms during the evolution of similar strains could also have played a role in determining this variability.
从四个欧洲国家（希腊、匈牙利、意大利和瑞典）分离出的10株产VIM-1样获得性金属β-内酰胺酶（MBLs）的多重耐药铜绿假单胞菌菌株，通过多种方法进行遗传相关性分析，包括鞭毛蛋白（fliC）序列分析、脉冲场凝胶电泳（PFGE）对基因组DNA进行宏观限制性图谱分析、随机扩增多态性DNA（RAPD）以及多位点序列分型（MLST）。这四种方法总体上产生了一致的结果，但在确定分离株之间的相关性方面显示出不同的分辨能力（PFGE>RAPD>MLST>fliC分型），并且可以有效地相互补充，以解决产获得性MBLs的铜绿假单胞菌菌株分子流行病学中的问题。特别是，最近开发的MLST方法在使用RAPD和PFGE不易发现分离株之间的克隆相关性时，有助于揭示这种相关性，并且表明目前在欧洲传播的一些VIM-1样MBL阳性铜绿假单胞菌菌株有共同的祖先。MBL产生菌属于三个克隆复合体/爆发组（BGs）。其中一个对应于先前描述的BG4，包括来自匈牙利和瑞典的O12血清型菌株，而另外两个是新的，包括来自希腊、瑞典和/或意大利的O11血清型或不可分型菌株。对各种分离株携带blaVIM-1样盒式结构的整合子进行比较，发现其结构存在显著异质性，这表明在同一克隆谱系的成员中可能发生了多个独立的获取不同含blaVIM整合子的事件，尽管在相似菌株的进化过程中整合酶介导的盒式结构改组或其他重组机制也可能在决定这种变异性方面发挥了作用。
