伤寒沙门菌耐药质粒pR_(ST98) spv毒力基因的研究  

Identification and molecular analysis of Salmonella plasmid virulence genes (spv) on antibiotic resistance plasmid pR_(ST98) from S.typhi

作　　者：黄瑞[1] 焦旸[1] 祁小飞[1] 张学光[2] 

机构地区：[1]苏州大学医学院微生物学教研室,215007 [2]苏州大学生命科学院

出　　处：《中华检验医学杂志》2005年第5期519-521,共3页Chinese Journal of Laboratory Medicine

基　　金：中国博士后基金 (中博基 2001 14);苏州大学医学发展基金(苏大 2003 2)

摘　　要：目的　研究多重耐药伤寒沙门菌耐药质粒pRST98是否具有沙门菌属中其他致病菌毒力质粒上的高度保守基因——spv,并对扩增的spv基因进行克隆及核酸序列测定。方法　对已确定能增强细菌毒力表型的耐药质粒pRST98,用spv基因特异引物进行PCR扩增和SPV探针的Southerblot分析,并将扩增到的spv基因片段装入克隆载体pGEM TEASY进行测序。结果　PCR和Southernblot结果显示,伤寒沙门菌耐药质粒pRST98上亦存在spv基因的同源序列spvR和spvB,其ORF分别为894bp和1 776bp,与鼠伤寒沙门菌毒力质粒上spv基因的同源性超过99%。结论　本研究从核酸水平首次证实伤寒沙门菌耐药质粒pRST98具有多效性,是既编码细菌抗药性又编码细菌毒力的“嵌合型”质粒。Objective To identify and analyze the plasmid (pR_ ST98 ) encoding multi-resistance to anti-microbial agents in S.typhi presenting the Salmonella plasmid virulence gene (spv).Methods Plasmid pR_ ST98 ,which could mediate virulence to its host bacteria, was used as the templete. The spv-specific PCR and Southern blot were employed to identify the spv virulence gene on this plasmid. The amplified spv fragments (spvR and spvB) were cloned into pGEM-T EASY.Then the DNA sequences were analysed. Results The date of PCR and Southern blot showed that spv,which had been found in other pathogenetic Salmonella spp. except S. typhi was also presented on pR_ ST98 . The ORF of spvR and spvB of pR_ ST98 were 894bp and 1 776bp respectively. They had more than 99% homologus with that of spvR and spvB on virulence plasmid in S.typhmurium.Conclusion From the results of PCR,Southern blot and nuclei acid sequencing, we concluded that this is the first report of revealing a mosaic-like plasmid carrying genes encoding not only drug resistance but also virulence in S.typhi.

关 键 词：质粒pRST98 毒力基因 Southern spv基因 pGEM-T 鼠伤寒沙门菌 毒力质粒 blot PCR扩增 细菌抗药性 保守基因 沙门菌属 多重耐药 序列测定 毒力表型 特异引物 克隆载体 基因片段 同源序列 核酸水平 细菌毒力 致病菌 SPV 同源性 

分 类 号：R378[医药卫生—病原生物学]