Expression control mechanisms of LEE pathogenic factors by AAA proteases in Enterohaemorrhagic and Enteropathogenic Eschericha coli

AAA蛋白酶在肠出血性和肠病性大肠杆菌中表达LEE致病因子的表达控制机制

• 批准号: 17590387
• 负责人: TOMOYASU Toshifumi
• 金额: $ 2.3万
• 依托单位: The University of Tokushima
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17590387/
• 关键词: Enterohemorrhagic E.coli; EHEC; LEE; Type III secretion system; AAA protease; ClpXP; Lon; GrlR; 腸管病原性大腸菌; ClpX; GrlR; H-NS

1. Enterohemorrhagic Escherichia coli (EHEC) and Enteropathogenic E. coli (EPEC) cause histopathological lesions of the intestinal epithelial cells that are known as attaching and effacing (A/E) lesions. Both strains carry a unique region of chromosomal DNA known as the locus for enterocyte effacement (LEE) that encodes a type III secretion system (TTSS) and virulence proteins. We have recently reported that AAA proteases (CIpXP, Lon) and molecular chaperones control 2 TTSSs in Salmonella Typhimurium: (i) flagellum biogenesis and (ii) the expression of the Pathogenicity Island 1. We demonstrated that the EHEC and EPEC clpPX mutants strongly impaired the secretion of virulence proteins by TTSS and repressed transcription from all the LEE promoters. The rpoS mutation in EHEC enhanced transcription from all the LEE promoters and the secretion of virulence proteins, and it could partially suppress the defects of the clpPX mutation. These data indicate that the EHEC ClpXP protease is a posi … More tive regulator for LEE expression, and this regulation occurs via 2 pathways: the o^<S->dependent and os-independent pathways.2. Recently, 2 LEE-encoded regulators-GrlA (global regulator of LEE activator) and GrlR (Grl repressor)-were identified. Iyoda et al. reported that ClpXP protease controls the expression of LEEpromoters via the regulation of GrlR levels in EHEC (J.Bacteriol. 2005. 187: 4086-94). However, the control mechanisms underlying the expression of LEEpromoters by Gr1A, GrlR, and AAA proteases remain unclear. Therefore, we established an assay system using nonpathogenic E. coli that enables analysis of the interaction among these proteins by measuring the activities of the LEE2, LEE3, and LEE5promoters. Our data revealed that the activation of ler (LEE-encoded regulator) expression by Gr1A entailed the participation of the domain that exists for a length of 131 base pairs downstream from the ler stop codon. Presently, we are analyzing the LEE expression control mechanisms exerted by Gr1R, Gr1A, and AAA proteases in detail. Less

1.肠出血性大肠埃希氏菌(EHEC)和致病性肠出血性大肠杆菌(EPEC)可引起肠上皮细胞的组织病理学损害，称为附着和消失(A/E)损害。这两种毒株都携带一个独特的染色体DNA区域，称为肠细胞消失基因(Lee)，编码III型分泌系统(TTSS)和毒力蛋白。我们最近报道了AAA酶(CIpXP，Lon)和分子伴侣控制着鼠伤寒沙门氏菌的两个TTSS：(I)鞭毛的生物发生和(Ii)致病岛1的表达。我们发现EHEC和EPEC clpPx突变体强烈地抑制TTSS分泌毒力蛋白，并抑制所有Lee启动子的转录。EHEC中的rpos突变促进了所有Lee启动子的转录和毒力蛋白的分泌，并能部分抑制clpPX突变的缺陷。这些数据表明，EHEC Clpxp蛋白酶是一种POSI…。对Lee的表达有更积极的调控作用，这种调节通过两条途径实现：依赖于和不依赖于OS的两条途径：S。最近发现了2个Lee编码的调节子--GrlA(Lee激活子的全球调节子)和GrlR(GRL抑制子)。Iyoda等人。报道称，ClpXP蛋白酶通过调节EHEC(J.Bacteriol.)中GrlR水平来调控LEE启动子的表达。2005年。187：4086-94)。然而，GR1a、GrlR和AAA酶对LEE启动子表达的调控机制尚不清楚。因此，我们建立了一个使用非致病性大肠杆菌的检测系统，该系统能够通过测量LEE2、LEE3和LEE5启动子的活性来分析这些蛋白质之间的相互作用。我们的数据显示，GR1A激活LER(Lee编码的调节器)表达需要LER终止密码子下游131个碱基对的结构域的参与。目前，我们正在详细分析Gr1R、GR1A和AAA蛋白水解酶对Lee基因表达的调控机制。较少

项目成果

The DnaK chaperone machinery converts the native F1hD2C2 hetero-tetramer into a functional transcriptional regulator of flagellar regulon expression in Salmonella.

DnaK 伴侣机制将天然 F1hD2C2 异源四聚体转化为沙门氏菌鞭毛调节子表达的功能性转录调节因子。

• 发表时间: 2006
• 期刊: Molecular Microbiology 59
• 作者: A.Takaya;M.Matsui;T.Tomoyasu;M.Kaya;T.Yamamoto.
• 通讯作者: T.Yamamoto.

C1pXP controls the expression of LEE genes in enterohaemorrhagic Escherichia coli.

C1pXP 控制肠出血性大肠杆菌中 LEE 基因的表达。

• 发表时间: 2005
• 期刊: FEMS Microbiol. Lett. 253(1)
• 作者: Juthaporn Kohwiwattanagun;Ikuo Kawamura;Takao Fujimura;et al.;Hiroyuki Yamaguchi;Tomoyasu T et al.
• 通讯作者: Tomoyasu T et al.

DnaK chaperone machinery converts the native F1hD2C2 hetero-tetramer into a functional transcriptional regulator of flagellar regulon expression in Salmonella.

DnaK 伴侣机制将天然 F1hD2C2 异源四聚体转化为沙门氏菌鞭毛调节子表达的功能性转录调节因子。

• 发表时间: 2006
• 期刊: Mol Microbiol. 59(4)
• 作者: Piao L-X.;Aosai F.;Mun H-S.;Yano A.;Taijin Kaku et al.;Aosai F.;Ryosuke Uchiyama et al.;Takaya A. et al.
• 通讯作者: Takaya A. et al.

The DnaK chaperone machinery converts the native FlhD2C2 hetero‐tetramer into a functional transcriptional regulator of flagellar regulon expression in Salmonella

• DOI: 10.1111/j.1365-2958.2005.05016.x
• 发表时间: 2006-02
• 期刊: Molecular Microbiology
• 影响因子: 3.6
• 作者: A. Takaya;M. Matsui;T. Tomoyasu;Michihiro Kaya;Tomoko Yamamoto

ClpXP controls the expression of LEE genes in enterohaemorrhagic Escberichia coli.

ClpXP 控制肠出血性大肠杆菌中 LEE 基因的表达。

• 发表时间: 2005
• 期刊: FEMS Microbiol. Lett. 253(1)
• 作者: Ryosuke Uchiyama;Ikuo Kawamura;Takao Fujimura;Michiko Kawanishi;Tomoyasu T. et al.
• 通讯作者: Tomoyasu T. et al.