多位点酶电泳法在新疆伤寒沙门氏菌分类和群体遗传学研究中的应用

采用多位点酶电泳（ＭＥＥ）法对新疆近１１年分离的１５４株伤寒沙门氏菌进行部分多位点酶基因型分类和群体遗传学研究。共测定分析７种代谢酶。研究结果表明,上述菌株共分为６９个电泳型（ＥＴ）,分属１０个克隆系（ＣＬａ～ＣＬｊ）,其中３０株爆发菌株分属２１个ＥＴｓ,３个ＣＬ（ＣＬｅ、ｆ和ｊ）,以ＥＴ１７、２０、２１、２４、２６和２７为主,占６１．３０％,ＣＬｆ为优势克隆系,菌株占９５．００％;７４株散发菌株

Application of Multilocus Enzyme Electrophoresis in Studies of Taxonomy and Population Genetics of S.typhi in Xinjiang

Multilocus enzyme electrophoresis (MEE) was employed to study the genotype taxon and population genetics of 154 isolates of S.typhi from Xinjiang in recent 11 years. Seven kinds of enzymes were examined and determined. One hundred and fifty-four strains of S.typhi were classified into 69 electroretic types (ETs) and 10 clones (CLa-CLj). Among those 154 strains 80 epidemic isolates belonged to 21 ETs and 3 clones (CLe, f, j). ET17, 20, 21, 24, 26, 27 were the main ETs (61.30%), and CLf was the dominant clone (95.00%). Seventy-four non-epidemic isolates belonged to 48 ETs and 9 clones (CLa, b, c, d, f, g, h, i, j), no obvious dominant ET was found in them, and the main clone CLh accounted for 43.30%. It demonstrated that both outbreak and sporadic epidemics could be caused by many strains of ETs and clones, but the distribution of the former ETs was more concentrated and the preponderance of clones was more obvious. The analyses on structure of population genetics indicated that all of 7 enzymes were polymorphic. Genetic diversity among the enzyme loci was quite high, with an average of 0.35 per locus (H). The average number of alleles per locus (h) was 6.14. There was no significant difference in h or H between the isolates of different sources (P>0.05). It was clear that S.typhi of different sources in Xinjiang were originated from the same population. The results also showed that there was a dominant allele in every enzyme locus. Natural selection was the main role in the evolution of S.typhi.