变性梯度凝胶电泳检测鲍曼不动杆菌中SHV基因单核苷酸多态性

目的建立变性梯度凝胶电泳（DGGE）检测超广谱β内酰歧酶（ESBL）基因中单核苷酸多态性（SNP）的方法，并获得鲍曼不动杆菌中SHV丛因SNP的资料。方法采用DGGE并结合DNA序列测定，检测了24株SHV基闳刚性的鲍曼不动杆菌SHV基因SNP。结果对这些菌株SHV基因的PCR产物直接进行DGGE电泳时，24例标本均呈现出单一条带，但条带的位置明显不同，可分为A、B两组；对两组标本分别用含GC后夹的引物进行SHV基因PCR扩增后再行DGGE，结果显示各产物均为单一条带，而且每组条带均处于同一位置。测序结果表明两组产物分别为SHV-1b．Like、SHV一18-Like。结论目前该地区鲍曼不动杆菌中SHV基因存在两种型别。通过DGGE，不仅能简便、迅速地获得某种基因的SNP资料，而且有利于高效和经济地筛选出新的核苷酸突变。

Detection of single nucleotide polymorphrism of SHV gene in Acinetobacter baumannii using Denaturing Gradient Gel-Electrophoresis

Objective To establish a method to detect single nucleotide polymorphrism（SNP）in genes of ESBLs by Denaturing gradient gel-electrophoresis （DGGE）, and to obtain the data on SNP of SHV gene in A.baumannii. Methods SNP of SHV was detected by DGGE and DNA sequencing in 24 strains in which SHV gene were positive. Results The direct DGGE to PCR products showed that there was single strip in all 24 samples, but the position of strips was different and could be classified to two groups（A or B）. After SHV gene was amplified by PCR with the primer involving ＂GC clamp＂, the PCR products of two groups were electrophoresed by DGGE, respectively. The results showed that there was still single strip with the same position in A or B group. DNA sequencing revealed that two groups were SHV-1b-Like and SHV-18-Like, respectively. Conclusion These suggested that there were two kinds of SHV gene in A.baumannii of our region. Meanwhile, we can obtain conveniently SNP data by DGGE but also screen out new nucleotide acid mutation efficiently and economically.