Pupo G M, Lan R, Reeves P R
Department of Microbiology, The University of Sydney, Sydney, New South Wales 2006, Australia.
Proc Natl Acad Sci U S A. 2000 Sep 12;97(19):10567-72. doi: 10.1073/pnas.180094797.
The evolutionary relationships of 46 Shigella strains representing each of the serotypes belonging to the four traditional Shigella species (subgroups), Dysenteriae, Flexneri, Boydii, and Sonnei, were determined by sequencing of eight housekeeping genes in four regions of the chromosome. Analysis revealed a very similar evolutionary pattern for each region. Three clusters of strains were identified, each including strains from different subgroups. Cluster 1 contains the majority of Boydii and Dysenteriae strains (B1-4, B6, B8, B10, B14, and B18; and D3-7, D9, and D11-13) plus Flexneri 6 and 6A. Cluster 2 contains seven Boydii strains (B5, B7, B9, B11, B15, B16, and B17) and Dysenteriae 2. Cluster 3 contains one Boydii strain (B12) and the Flexneri serotypes 1-5 strains. Sonnei and three Dysenteriae strains (D1, D8, and D10) are outside of the three main clusters but, nonetheless, are clearly within Escherichia coli. Boydii 13 was found to be distantly related to E. coli. Shigella strains, like the other pathogenic forms of E. coli, do not have a single evolutionary origin, indicating convergent evolution of Shigella phenotypic properties. We estimate the three main Shigella clusters to have evolved within the last 35,000 to 270,000 years, suggesting that shigellosis was one of the early infectious diseases of humans.
通过对染色体四个区域的八个管家基因进行测序，确定了代表四种传统志贺氏菌属（亚群）（痢疾志贺氏菌、福氏志贺氏菌、鲍氏志贺氏菌和宋内志贺氏菌）各血清型的46株志贺氏菌的进化关系。分析显示每个区域都有非常相似的进化模式。鉴定出三株菌株簇，每个簇都包括来自不同亚群的菌株。簇1包含大多数鲍氏志贺氏菌和痢疾志贺氏菌菌株（B1 - 4、B6、B8、B10、B14和B18；以及D3 - 7、D9和D11 - 13）加上福氏志贺氏菌6型和6A型。簇2包含七株鲍氏志贺氏菌菌株（B5、B7、B9、B11、B15、B16和B17）和痢疾志贺氏菌2型。簇3包含一株鲍氏志贺氏菌菌株（B12）和福氏志贺氏菌血清型1 - 5菌株。宋内志贺氏菌和三株痢疾志贺氏菌菌株（D1、D8和D10）在三个主要簇之外，但仍明显属于大肠杆菌。发现鲍氏志贺氏菌13型与大肠杆菌关系较远。志贺氏菌菌株与大肠杆菌的其他致病形式一样，并非有单一的进化起源，这表明志贺氏菌表型特性是趋同进化的结果。我们估计这三个主要的志贺氏菌簇是在过去35000至270000年内进化而来的，这表明志贺氏菌病是人类早期的传染病之一。
