基因多态性分析在凝固酶阴性葡萄球菌菌种鉴定中的应用

目的建立快速凝固酶阴性葡萄球（CNS）菌种的基因鉴定方法。方法对培养获得的、经Auto Scan-4微生物分析仪和API Staph鉴定系统鉴定为CNS的100株临床分离菌株和质控菌株应用tRNA基因间长度多态性PCR分析（tDNA-PCR）和肠杆菌基因间相同序列（ERIC）两种分子生物学方法进行常见的CNS菌种鉴定，同时改良实验条件，并将tDNA-PCR及ERIC-PCR两种分子生物学方法的鉴定结果与传统的Auto Scan-4微生物分析仪和API Staph鉴定系统进行比较。结果tDNA-PCR及ERIC-PCR两种分子生物学方法对质控菌株及经Auto Scan-4微生物分析仪和API Staph系统鉴定的12种临床分离CNS菌株均可以得到各自不同的电泳图谱，它们可以快速、准确地对常见12种CNS，包括表皮葡萄球菌、溶血葡萄球菌、人葡萄球菌、华纳葡萄球菌、模仿葡萄球菌、孔氏葡萄球菌、心耳葡萄球菌、松鼠葡萄球菌、头状葡萄球菌、施氏葡萄球菌、木糖葡萄球菌和里昂葡萄球菌进行菌种鉴定。从图谱的肉眼观察看，12种CNS均可以很好地鉴别开。tDNA-PCR及ERIC-PCR与Auto Scan-4和API Staph鉴定系统的一致率为95％。经Taq酶聚合后进行电泳，tDNA-PCR在100～600bp产生6～10条DNA片段；ERIC-PCR在100～1200bp仅产生1～8条DNA片段。结论tDNA-PCR及ERIC-PCR是快速、敏感的CNS菌种鉴定的方法，具有高度的特异性。

Application of PCR for identification of coagulase-negative Staphylococcus

Objective To set up a rapid identification of Coagulase-negative Staphylococcus.Methods One hundred strains of Clinical isolates identified as members of the CNS by Auto Scan-4 and API Staph system. were subjected to be identified to the species level with moleculat methods of tRNA gene intergenic spacer length polymorphism (tDNA-ILP) and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR).The comparison was conducted among the results of tDNA-ILP,ERIC-PCR and Auto Scan-4 and API Staph system.Results tDNA -PCR and ERIC -PCR exhibited accurately for identification of 11 kinds of clinical CNS isolates,such as S.epidermidis,S.haemolyticus,S.hominis S.warneri,S.simulans,S.cohhni,S.auricularis,S.sciuri,S.capitis,S.schleiferi,S.xylosus,and S.lugdunensis.The coincidency of the methods between Auto Scan-4, API Staph and tDNA-PCR, ERIC -PCR was 95%.Taq tDNA-PCR yielded profiles of 6~10 bands ranging in size from 100-600 bp, and ERIC-PCR yielded profiles of 1-8 bands ranging in size from 100-600 bp.Conclusion Both tDNA-PCR and ERIC-PCR were a methods for accurate, rapid, and sensitive identify ication of 11 kinds of clinical CNS isolates.