Blaser M J, Miotto K, Hopkins J A
Medical Research Service, Department of Veterans Affairs Medical Center, Denver, CO.
Int J Epidemiol. 1992 Jun;21(3):594-8. doi: 10.1093/ije/21.3.594.
Fourteen strains of Shigella dysenteriae type 1 (Shiga bacillus) isolated from people in diverse locations from 1940 to 1987 were studied. Southern hybridization with three cloned Escherichia coli genes, Shiga-like toxin I (SLTI), frd, and ompF, was used to determine restriction fragment length polymorphism (RFLP) of the genomic DNA of these strains. Digestion with each of four restriction endonucleases generated fragments of identical size to which the frd and ompF hybridized for each of the 14 strains, indicating the conservation of these genes and their flanking sequences. In contrast, after digestion with HindIII, EcoRV, and ClaI and probing with SLTI, there were RFLP among the strains. The results showed three clones of the Shiga bacillus, and suggested that dissemination of a single clone may continue for decades within a wide geographical area.
对1940年至1987年期间从不同地点人群中分离出的14株痢疾志贺氏菌1型（志贺杆菌）进行了研究。利用与三种克隆的大肠杆菌基因——志贺样毒素I（SLTI）、frd和ompF进行Southern杂交，来确定这些菌株基因组DNA的限制性片段长度多态性（RFLP）。用四种限制性内切酶中的每一种进行消化，产生的片段大小相同，14株菌株中的每一株的frd和ompF都能与之杂交，这表明这些基因及其侧翼序列具有保守性。相比之下，在用HindIII、EcoRV和ClaI消化并用SLTI进行探针杂交后，菌株之间存在RFLP。结果显示志贺杆菌有三个克隆，并表明单个克隆可能在广阔的地理区域内持续传播数十年。
