左氧氟沙星对金黄葡萄球菌小RNA表达的影响  

Effects of levofloxacin on small RNA expression in Staphylococcus aureus

作　　者：宋娟[1,2] 楚雍烈[1] 

机构地区：[1]西安交通大学免疫与病原生物学系,陕西西安710061 [2]法国里昂第一大学,法国里昂69008

出　　处：《中国病原生物学杂志》2012年第2期94-97,128,共5页Journal of Pathogen Biology

摘　　要：目的研究左氧氟沙星对金黄葡萄球菌小RNA表达的影响及对细菌生长的作用。方法分别在不同抑菌浓度左氧氟沙星干扰情况下,培养金黄葡萄球菌实验株RN6390和RN1HG001,提取RNA,用实时定量逆转录聚合酶链反应(qRT-PCR)检测不同菌株中RNAⅢ、RsaA、RsaE、RsaG、RsaH的含量,比较不同抑菌浓度左氧氟沙星作用下小RNA的表达差异。结果在MH培养液和BH培养液中左氧氟沙星对RN6390和RN1HG001的MIC均为0.25μg/ml。5种小RNA中,RNAⅢ的表达量最多,RsaG最少;当左氧氟沙星浓度≥1/4MIC时,开始对金黄葡萄球菌的生长产生明显抑制作用,5种小RNA的表达均开始下降;在RN6390菌株,1/16 MIC和1/8 MIC的左氧氟沙星能促进RsaH表达。结论不同浓度左氧氟沙星对金黄葡萄球菌小RNA表达具有抑制或者促进作用,提示除了其本身具有的阻碍细菌DNA合成的功能外还可能影响细菌基因的转录。Objective To study the effects of levofloxacin on the expression of small RNAs in Staphylococcus aureus and its effect on bacterial growth.Methods Two S.aureus lab strains,RN6390 and RN1HG001,were cultured in the presence of different concentrations of levofloxacin.Then RNA was isolated from the bacterial culture.Afterwards,qRT-PCR was used to detect RNAⅢ,RsaA,RsaE,RsaG,and RsaH production.Data analysis compared the changes in expression of the 5 sRNAs in the presence of different concentrations of levofloxacin.Results The MIC of levofloxacin on RN6390 and RN1HG001 in BH medium was identical to that in MH medium（0.25 μg/ml）.Among the 5 sRNAs,RNAⅢ was expressed the most while RsaG was expressed the least.A concentration of levofloxacin above 1/4 MIC markedly suppressed the growth of RN6390 and RN1HG001.At a concentration of levofloxacin above 1/4 MIC,the expression of all of the sRNAs started to decrease.The RsaH level in RN6390 increased in the presence of 1/16 MIC or 1/8 MIC levofloxacin.Conclusion Levofloxacin can either promote or suppress sRNA expression depending on its concentration.Apart from its role in blocking DNA replication,it may also affect gene transcription.

关 键 词：金黄葡萄球菌 左氧氟沙星 小RNA QRT-PCR 

分 类 号：R378.11[医药卫生—病原生物学]