摘要
转座子是一种能够在转座酶作用下随机插入到宿主基因组中的DNA可移动元件,常被用作挖掘宿主功能基因的工具。细菌宿主限制性修饰系统(R-M)能够稳定基因组,抑制转座子插入基因组中。为了分析沙门菌R-M系统对外源转座子插入的抑制效应,本研究利用自杀质粒的方法构建SL1344的hsdM基因缺失株,制备其相应的Mini-Tn5和TnSC189转座子突变库,通过平板计数,计算并比较转座效率,分析hsdM基因对转座子转座效率的抑制效应。结果显示,Mini-Tn5和TnSC189转座子对S06004的转座效率均显著高于SL1344和C50041,TnSC189对三种血清型沙门菌转座效率均高于Mini-Tn5。而hsdM基因缺失显著提高了对SL1344的转座效率,表明hsdM基因表达对转座子基因组插入存在显著的抑制效应。本研究证实,沙门菌hsdM基因能够抑制外源转座子插入和维持基因组稳定性的功能,为hsdM基因稳定基因组的机制研究奠定了基础。
Transposons are movable elements of DNA that can randomly insert into host’s genome by transposase,which is usually used to excavate functional genes.But the bacterial host restriction and modification(R-M)system can make genome stable,which may inhibit transposons insertion.And so,in order to study the inhibitory effect of R-M system to transposons insertion,hsd M mutant and its transposon mutant library were constructed,bacterial colonies on LB plates with and without antibiotics were counted respectively,then transposon transposition efficiency was calculated and compared to analyze the effect of hsd M gene.The results showed that the Mini-Tn5 and Tn SC189 transposition efficiency in Salmonella Pullorum S06004 were higher than that in Salmonella Enteritidis C50041 and Salmonella Typhimurium SL1344.Compared with Mini-Tn5,the Tn SC189 had higher transposition efficiency in three Salmonella serovars.The loss of hsd M gene significantly increased Mini-Tn5 and Tn SC189 transposition efficiency in SL1344,which indicated that hsd M gene had a inhibitory effect on the transposons.This study confirmed that hsd M gene could inhibit foreign transposons insertion and maintain the stability of Salmonella genome,it would offer a base for the mechanism of hsd M gene on the stability of genome.
作者
刘桂凤
钱天瑶
黄鹏
王耀楠
耿士忠
焦新安
LIU Gui-feng;QIAN Tian-yao;HUANG Peng;WANG Yao-nan;GENG Shi-zhong;JIAO Xin-an(Key Laboratory of Prevention and Control of Biological Hazard Factors(Animal Origin)for Agrifood Safety and Quality,Ministry of Agriculture of China/Key Laboratory of Zoonoses of Jiangsu Province/Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses,Yangzhou University,Yangzhou 225009,China)
出处
《中国兽医科学》
CAS
CSCD
北大核心
2021年第11期1426-1432,共7页
Chinese Veterinary Science
基金
国家重点研发计划项目(2016YFD0501607)
江苏省自然科学基金项目(BK20151306)
江苏省重点研发计划项目(BE2018334)
江苏省重点实验室开放课题(0273896034819)。
