The Expression of the fim Operon Is Crucial for the Survival of Streptococcus parasanguinis FW213 within Macrophages but Not Acid Tolerance.
The Expression of the fim Operon Is Crucial for the Survival of Streptococcus parasanguinis FW213 within Macrophages but Not Acid Tolerance.
复制标题
DOI：
10.1371/journal.pone.0066163
复制
发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Chang YC
中科院分区：
文献类型：
--
作者：
Chen YY;Shieh HR;Chang YC
过渡金属离子的获得对于细菌中毒力基因的生存力和在某些情况下的表达是必不可少的。副血链球菌FW 213的fimCBA操纵子编码一个Mn ~（2+）/Fe ~（2+）特异性ATP结合盒转运蛋白。FimA是该系统中的一种脂蛋白，可能通过与受损心脏组织上的纤维蛋白单层结合而对心内膜炎的发展至关重要。最近的序列分析表明，Spaf_0344是同源的链球菌gordonii scaR，编码金属调节蛋白的Sca Mn 2+特异性转运。基于同源性，将Spaf_0344命名为fimR。通过使用不同的fim启动子（pfim）衍生物融合无启动子氯霉素乙酰转移酶基因，pfim的顺式元件的功能进行了分析，在野生型和fimR缺陷型主机。结果表明，FimR抑制pfim的表达，fimC的5′回文序列参与了pfim的抑制。通过体外电泳凝胶迁移率变动试验和体内染色质免疫沉淀试验（ChIP）-定量实时PCR（qPCR）进一步证实了FimR与回文序列之间的直接相互作用。ChIP-qPCR分析的结果还表明，FimR被Mn 2+激活，并且在较小程度上被Fe 2+激活。功能分析表明，FimA在S. parasanguinis对野生型抗氧化应激和吞噬细胞内的存活水平至关重要，但对酸耐受性无关。综上所述，除了作为粘附素（FimA）外，fim操纵子的表达对于S.副血吸虫
The acquisition of transition metal ions is essential for the viability and in some cases the expression of virulence genes in bacteria. The fimCBA operon of Streptococcus parasanguinis FW213 encodes a Mn2+/Fe2+-specific ATP-binding cassette transporter. FimA, a lipoprotein in the system, is essential for the development of endocarditis, presumably by binding to fibrin monolayers on the damaged heart tissue. Recent sequence analysis revealed that Spaf_0344 was homologous to Streptococcus gordonii scaR, encoding a metalloregulatory protein for the Sca Mn2+-specific transporter. Based on the homology, Spaf_0344 was designated fimR. By using various fim promoter (pfim) derivatives fused with a promoterless chloramphenicol acetyltransferase gene, the functions of the cis-elements of pfim were analyzed in the wild-type and fimR-deficient hosts. The result indicated that FimR represses the expression of pfim and the palindromic sequences 5′ to fimC are involved in repression of pfim. A direct interaction between FimR and the palindromic sequences was further confirmed by in vitro electrophoresis gel mobility shift assay and in vivo chromatin immunoprecipitation assay (ChIP)-quantitative real-time PCR (qPCR). The result of the ChIP-qPCR analysis also indicated that FimR is activated by Mn2+ and, to a lesser degree, Fe2+. Functional analysis indicated that the expression of FimA in S. parasanguinis was critical for wild-type levels of survival against oxidative stress and within phagocytes, but not for acid tolerance. Taken together, in addition to acting as an adhesin (FimA), the expression of the fim operon is critical for the pathogenic capacity of S. parasanguinis.
登录
查看更多内容
影响因子：
7.6
作者：
COLE, RM;CALANDRA, GB;NUGENT, KM
通讯作者：
NUGENT, KM
影响因子：
3.6
作者：
Gaudu, P;Lamberet, G;Gruss, A
通讯作者：
Gruss, A
影响因子：
3.1
作者：
Hanks, Tracey S.;Liu, Mengyao;Lei, Benfang
通讯作者：
Lei, Benfang
影响因子：
4.4
作者：
DUNNY, GM;LEE, LN;LEBLANC, DJ
通讯作者：
LEBLANC, DJ
影响因子：
3.8
作者：
Anderton, Julie M.;Rajam, Gowrisankar;Ades, Edwin W.
通讯作者：
Ades, Edwin W.