Dingle Kate E, Colles Frances M, Falush Daniel, Maiden Martin C J
Nuffield Department of Clinical Sciences, Oxford University, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom.
J Clin Microbiol. 2005 Jan;43(1):340-7. doi: 10.1128/JCM.43.1.340-347.2005.
A multilocus sequence typing (MLST) scheme that uses the same loci as a previously described system for Campylobacter jejuni was developed for Campylobacter coli. The C. coli-specific primers were validated with 53 isolates from humans, chickens, and pigs, together with 15 Penner serotype reference isolates. The nucleotide sequence of the flaA short variable region (SVR) was determined for each isolate. These sequence data were compared to equivalent information for 17 C. jejuni isolates representing the known genetic diversity of this species. C. coli and C. jejuni share approximately 86.5% identity at the nucleotide sequence level within the MLST loci. There is evidence of genetic exchange of the housekeeping genes between the two species, but at a very low rate; only one sequence type from each species showed evidence of imported DNA. The flaA gene was more variable and has been exchanged many times between the two species, making it an unreliable marker for species identification but useful for distinguishing closely related strains. All but 3 of 21 human C. coli clinical isolates were distinct, according to the combined MLST and SVR sequences. The use of a common MLST scheme allows direct comparisons of the population biology and molecular epidemiology of these two closely related human pathogens.
我们为空肠弯曲菌开发了一种多位点序列分型（MLST）方案，该方案使用与先前描述的空肠弯曲菌系统相同的基因座。用来自人类、鸡和猪的53株分离株以及15株彭纳血清型参考分离株对空肠弯曲菌特异性引物进行了验证。测定了每个分离株flaA短可变区（SVR）的核苷酸序列。将这些序列数据与代表该物种已知遗传多样性的17株空肠弯曲菌分离株的等效信息进行了比较。在MLST基因座内，空肠弯曲菌和空肠弯曲菌在核苷酸序列水平上的同一性约为86.5%。有证据表明这两个物种之间的管家基因发生了遗传交换，但频率非常低；每个物种只有一种序列类型显示出导入DNA的证据。flaA基因变异更大，并且在这两个物种之间已经多次交换，这使得它成为物种鉴定的不可靠标记，但有助于区分密切相关的菌株。根据MLST和SVR序列的组合，21株人类空肠弯曲菌临床分离株中除3株外均不相同。使用通用的MLST方案可以直接比较这两种密切相关的人类病原体的群体生物学和分子流行病学。
