文献类型：期刊文献

英文题名：Xenogeneic nucleoid-associated EnrR thwarts H-NS silencing of bacterial virulence with unique DNA binding

作者：Ma, Ruiqing[1,6];Liu, Yabo[1];Gan, Jianhua[5];Qiao, Haoxian[1];Ma, Jiabao[1];Zhang, Yi[1];Bu, Yifan[1];Shao, Shuai[1,4];Zhang, Yuanxing[1,3,4];Wang, Qiyao[1,2,4]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Qingdao Natl Lab Marine Sci & Technol, Lab Marine Fisheries Sci & Food Prod Proc, Qingdao 266071, Peoples R China;[3]Southern Marine Sci & Engn Guangdong Lab Zhuhai, Zhuhai 519000, Peoples R China;[4]Shanghai Engn Res Ctr Maricultured Anim Vaccines, Shanghai 200237, Peoples R China;[5]Fudan Univ, Sch Life Sci, State Key Lab Genet Engn,Shanghai Publ Hlth Clin, Collaborat Innovat Ctr Genet & Dev,Dept Biochem &, Shanghai 200438, Peoples R China;[6]Fudan Univ, Shanghai Publ Hlth Clin Ctr, Key Lab Med Mol Virol MOE MOH, Shanghai 201508, Peoples R China

年份：2022

卷号：50

期号：7

起止页码：3777

外文期刊名：NUCLEIC ACIDS RESEARCH

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000778033000001)】；

基金：National Key Research and Development Program of China [2018YFD0900504 to Q.W.]; National Natural Science Foundation of China [32130108 to Q.W.]; Shanghai Municipal Science and Technology Commission of Shanghai Outstanding Technology Leaders plan [21XD1431900 to Q.W.]; Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) [311020005 to Y.X.Z.]; China Agriculture Research System of MOF and MARA [CARS-47-17 to Q.W.].

语种：英文

摘要：Type III and type VI secretion systems (T3/T6SS) are encoded in horizontally acquired genomic islands (GIs) that play crucial roles in evolution and virulence in bacterial pathogens. T3/T6SS expression is subjected to tight control by the host xenogeneic silencer H-NS, but how this mechanism is counteracted remains to be illuminated. Here, we report that xenogeneic nucleoid-associated protein EnrR encoded in a GI is essential for virulence in pathogenic bacteria Edwardsiella and Salmonella. We showed that EnrR plays critical roles in T3/T6SS expression in these bacteria. Various biochemical and genetic analyses demonstrated that EnrR binds and derepresses the promoter of esrB, the critical regulator of T3/T6SS, to promote their expression by competing with H-NS. Additionally, EnrR targets AT-rich regions, globally modulates the expression of similar to 363 genes and is involved in various cellular processes. Crystal structures of EnrR in complex with a specific AT-rich palindromic DNA revealed a new DNA-binding mode that involves conserved HTH-mediated interactions with the major groove and contacts of its N-terminal extension to the minor groove in the symmetry-related duplex. Collectively, these data demonstrate that EnrR is a virulence activator that can antagonize H-NS, highlighting a unique mechanism by which bacterial xenogeneic regulators recognize and regulate foreign DNA.