中文摘要：

目的探讨单碱基靶点分子探针设计模型，并应用设计的分子信标探针检测结核杆菌耐乙胺丁醇embB 285 codon点突变，并与测序结果比较以验证。方法运用软件Beacon designer设计embB基因包含285codon的分子信标，应用荧光分光光度计检测embB 285 codon扩增片段与探针杂交后荧光信号，同时对扩增产物测序并作比较。结果通过荧光分光光度计观测到结核标准株及耐乙胺丁醇embB 285 codon PCR产物与分子信标杂交后荧光信号差异存在统计学意义；33株耐乙胺丁醇组与10株H37RV标准株对照组荧光信号强度比较，耐乙胺丁醇组embB 285 codon突变检出率为15％，测序法突变检出率为15％。结论分子信标技术对单碱基靶点突变具有较高的检出率；应用荧光分光光度计直接检测液相杂交荧光具灵敏、简单、准确等优点。

英文摘要：

Objective To study the model of design molecular probe detecting single basyl site and detecting.embB 285codou of Ethambutol resistant MTB by designed molecular beacon probe, meanwhile, to prove the way by confer to the soqueneing. Methods The software, Beaeon designer, was used to design the molecular beaeon of embB 285 eodon and detecting fluorescence signal from hybridization between the amplified product and probe, and compare between the way and sequencing of the amplification products. Results The differe~tween PCR products from standard strain and Ethambutol resistant one is obvious in detecting the fluorescent light by use of fluorescence speetrophotometer. We detected fluorescent light signal between the 33 Ethambutol resistant strains and 10 H37RV standard strains. The rate of resistant Ethambutol detected is about 15 %, and the rate of sequencing is about 15 %. Conclusion The efficiency of moleeular beaeon detecting single basyl site is good. Fluorescence speetrophotomcter have characteristics such as high sensitiveness） simple and accurate to directly detect the fluorescent light in liquid.