Iron Regulates Expression of Bacillus cereus Hemolysin II via Global Regulator Fur
Iron Regulates Expression of Bacillus cereus Hemolysin II via Global Regulator Fur
复制标题
铁通过全局调节因子 Fur 调节蜡状芽孢杆菌溶血素 II 的表达
作者：
E. Sineva;A. Shadrin;E. Rodikova;Zhanna Andreeva;A. Protsenko;S. Mayorov;D. Y. Galaktionova;Erica M Magelky;A. Solonin
摘要 病原体对环境信号（例如铁浓度）做出反应的能力是细菌生存和成功感染的关键。蜡样芽孢杆菌是一种分布广泛的细菌，具有独特的致病特性。溶血素 II (HlyII) 是一种成孔细胞毒素，在许多细胞和动物模型中已被证明与细菌致病性有关。与许多其他蜡状芽胞杆菌致病因子不同，HlyII 不受多效性转录调节因子 PlcR 的调节，而是受其自身调节因子 HlyIIR 的控制。结合体内和体外技术，我们发现 hlyII 表达也通过全局调节因子 Fur 通过与 hlyII 启动子直接相互作用而受到铁的负调节。 DNase I 足迹和体外转录实验表明 Fur 可阻止 RNA 聚合酶与 hlyII 启动子结合。 HlyII 表达谱表明，HlyIIR 和 Fur 以协调一致的方式调节 HlyII 表达，其中 Fur 的作用在细菌生长的早期阶段最大。总之，这些结果表明 Fur 作为 hlyII 表达的转录抑制因子。
ABSTRACT The capacity of pathogens to respond to environmental signals, such as iron concentration, is key to bacterial survival and establishment of a successful infection. Bacillus cereus is a widely distributed bacterium with distinct pathogenic properties. Hemolysin II (HlyII) is one of its pore-forming cytotoxins and has been shown to be involved in bacterial pathogenicity in a number of cell and animal models. Unlike many other B. cereus pathogenicity factors, HlyII is not regulated by pleiotropic transcriptional regulator PlcR but is controlled by its own regulator, HlyIIR. Using a combination of in vivo and in vitro techniques, we show that hlyII expression is also negatively regulated by iron by the global regulator Fur via direct interaction with the hlyII promoter. DNase I footprinting and in vitro transcription experiments indicate that Fur prevents RNA polymerase binding to the hlyII promoter. HlyII expression profiles demonstrate that both HlyIIR and Fur regulate HlyII expression in a concerted fashion, with the effect of Fur being maximal in the early stages of bacterial growth. In sum, these results show that Fur serves as a transcriptional repressor for hlyII expression.
噬菌体 T4 AsiA 对大肠杆菌 RNA 聚合酶的抑制。
DOI：
10.1006/jmbi.1998.1742
发表时间：
1998
期刊：
Journal of molecular biology.
影响因子：
--
作者：
Severinova,E;Severinov,K;Darst,SA
通讯作者：
Darst,SA
影响因子：
2.8
作者：
Budarina, ZI;Nikitin, DV;Severinov, K
通讯作者：
Severinov, K