sahH基因在变异链球菌LuxS缺陷株内表达对胞外多糖合成的影响  

Function of sahH gene in exopolysaccharides synthesis of Streptococcus mutans LuxS null strain

作　　者：胡戌琛 王玉霞 江文欣 牛晨光[1] 林文珍 黄正蔚[1] HU Xu-chen;WANG Yu-xia;JIANG Wen-xin;NIU Chen-guang;LIN Wen-zhen;HUANG Zheng-wei(National Clinical Research Center of Stomatology,Shanghai Key Laboratory of Stomatology&Shanghai Research Institute of Stomatology,Department of Endodontics,Shanghai Ninth People′s Hospital,Shanghai Jiao Tong University School of Medicine,Shanghai 200011,China;Department of Endodontics,Tianjin Stomatological Hospital&Hospital of Stomatology,Nankai University,Tianjin 300041,China)

机构地区：[1]上海交通大学医学院附属第九人民医院牙体牙髓科,上海市口腔医学重点实验室/上海市口腔医学研究所,国家口腔疾病临床研究中心,上海200011 [2]天津市口腔医院/南开大学口腔医院牙体牙髓科,天津300041

出　　处：《上海交通大学学报（医学版）》2018年第3期254-258,共5页Journal of Shanghai Jiao tong University:Medical Science

基　　金：国家自然科学基金(81570964)(NationalNaturalScienceFoundationofChina,81570964)

摘　　要：目的·研究sahH基因在变异链球菌LuxS缺陷株内的表达对其胞外多糖合成的影响。方法·以构建的LuxS缺陷株转有sahH基因的sahH+LuxS-SmUA159、LuxS缺陷株转有空质粒的PIB169+LuxS-SmUA159(背景对照)及变异链球菌SmUA159野生株为研究模型。实时荧光定量PCR观察胞外多糖合成相关基因的转录水平,蒽酮法观察生物膜胞外多糖合成情况。结果·与SmUA159和PIB169+LuxS-SmUA159菌株相比,sahH基因转入株sahH+LuxS-SmUA159的4种被检测基因(gtfA、gtfB、gtfC、gtfD)中,gtfA和gtfD转录水平有显著差异(均P<0.05),而gtfB和gtfC无明显差异。SmUA159、PIB169+LuxS-SmUA159和sahH+LuxS-SmUA159胞外多糖合成量无明显差异。结论·sahH基因转入可影响变异链球菌胞外多糖合成相关基因的表达,但不影响细菌总体胞外多糖合成量。Objective·To investigate the function of sahH gene in exopolysaccharides synthesis of Streptococcus mutans LuxS null strain.Methods·sahH+luxS-SmUA159 was constructed by introducing sahH gene into Streptococcus mutans LuxS null strain,while PIB169+luxS-SmUA159 and its wild strain SmUA159 were used as vector control and blank control.Real-time qPCR and anthrone test were performed to investigate the differences in exopolysaccharides synthesis among sahH+luxS-SmUA159,PIB169+luxS-SmUA159 and the wide-type strain SmUA159.Results·The transcriptional levels of gtfA and gtfD were upregulated in the sahH+luxS-SmUA159,compared to SmUA159 and PIB169+luxS-SmUA159(both P<0.05),but there was no statistical difference in the transcriptional levels of gtfB and gtfC.The results of the anthrone test showed exopolysaccharides synthesis of the three groups was also similar.Conclusion·sahH gene affects the expression of some genes related to exopolysaccharides synthesis,but it has little effect on the whole content of bacterial exopolysaccharides.

关 键 词：变异链球菌 胞外多糖 基因表达 细菌 sahH基因 

分 类 号：R378.12[医药卫生—病原生物学]