Sirisriro Thanatcha, Sethabutr Orntipa, Mason Carl, Talukder Kaisar A, Venkatesan Malabi M
Department of Enteric Diseases, Armed Forces Research Institute of Medical Science, Bangkok, Thailand.
J Microbiol Methods. 2006 Dec;67(3):487-95. doi: 10.1016/j.mimet.2006.05.004. Epub 2006 Jul 11.
Amplified fragment length polymorphism (AFLP) can be used to assess the genetic diversity of closely related microbial genomes. In this study, the first of its kind for identification of Shigella, the high discriminatory power of AFLP has been used to determine the genetic relatedness of 230 isolates of Shigella flexneri and Shigella sonnei strains. An AFLP database was generated to demonstrate its utility in the discrimination of closely related strains. Based on AFLP, S. flexneri strains could be grouped into separate clusters according to their serotypes. Within each serotype, strains demonstrated 80-100% similarity indicating that identical strains and closely related strains could be distinguished by this technique. S. flexneri 6 formed a distinct cluster with 55% similarity to the rest of the S. flexneri strains showing significant divergence from the rest of the S. flexneri strains. Significantly, S. sonnei isolates formed a distinct group and showed approximately the same level of genetic linkage to S. flexneri as Escherichia coli strains. Untypable isolates that showed conflicting agglutination reactions with conventional typing sera were identifiable by AFLP. Thus AFLP can be used for genetic fingerprinting of Shigella strains and aid in the identification of variant untypable isolates.
扩增片段长度多态性（AFLP）可用于评估密切相关的微生物基因组的遗传多样性。在本项针对志贺氏菌鉴定的首次此类研究中，AFLP的高鉴别力已被用于确定230株福氏志贺氏菌和宋内氏志贺氏菌菌株的遗传相关性。构建了一个AFLP数据库以证明其在鉴别密切相关菌株方面的效用。基于AFLP，福氏志贺氏菌菌株可根据其血清型分为不同的簇。在每个血清型内，菌株表现出80 - 100%的相似性，表明该技术可区分相同菌株和密切相关的菌株。福氏志贺氏菌6型形成了一个独特的簇，与其他福氏志贺氏菌菌株的相似性为55%，显示出与其他福氏志贺氏菌菌株有显著差异。值得注意的是，宋内氏志贺氏菌分离株形成了一个独特的组，并且与福氏志贺氏菌的遗传连锁水平与大肠杆菌菌株大致相同。通过AFLP可鉴定出与传统分型血清发生凝集反应冲突的无法分型的分离株。因此，AFLP可用于志贺氏菌菌株的基因指纹分析，并有助于鉴定变异的无法分型的分离株。
