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。肠肠肠肠肠球菌（EHEC）和肠病大肠杆菌（EPEC）引起肠上皮细胞的组织病理病变，这些细胞被称为附着和递增（A/E）病变。这两种菌株均具有独特的染色体DNA区域，称为肠球菌能量（LEE），该区域编码III型分泌系统（TTSS）和病毒蛋白质。 We have recently reported that AAA proteins (CIpXP, Lon) and molecular chainanes control 2 TTSSs in Salmonella Typhimurium: (i) flagelum biogenesis and (ii) the expression of the Pathogenicity Island 1. We demonstrated that the EHEC and EPEC clpPX mutants strongly impaired the secretion of virus proteins by TTSS and reproduced transcription from all the LEE promoters. EHEC中的RPO突变增强了所有Lee启动子和病毒蛋白的分泌的转录，并且可以部分抑制CLPPX突变的缺陷。这些数据表明EHEC CLPXP蛋白酶是Lee表达的POSI…更稳定的调节剂，并且该调节通过2个途径进行：O^<s->依赖性和与OS无关的途径。2。最近，已确定了2个LEE编码的调节器GRLA（Lee Activator的全局调节剂）和GRLR（GRL复制器）。 Iyoda等。报道CLPXP蛋白酶通过EHEC中的GRLR水平的调节来控制白细胞的表达（J.Bacteriol。2005。187：4086-94）。然而，GR1A，GRLR和AAA蛋白表达闪光剂表达的控制机制尚不清楚。因此，我们使用非致病性大肠杆菌建立了一个评估系统，该系统可以通过测量LEE2，LEE3和LEE5促进剂的活性来分析这些蛋白质之间的相互作用。我们的数据表明，GR1A的LER（LEE编码调节器）表达的激活需要从LER终止密码子下游的131个碱基对的域的参与。目前，我们正在详细分析GR1R，GR1A和AAA蛋白酶施加的Lee表达控制机制。较少的

项目成果

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.

Clp XP controls the expression of LEE genes genes enterohaemorrhagic Escherichoa coli.

Clp XP 控制肠出血性大肠杆菌 LEE 基因的表达。

• 发表时间: 2005
• 期刊: FEMS Microbiol. Lett. 253・1
• 作者: Tomoyasu;T et al.
• 通讯作者: T et al.

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.