Comprehensive analyses of bacterial pathogenesis based on the genome information

本研究以三株重要病原菌的基因组序列为基础，对它们的致病机理和基因组多样性进行了综合分析，获得了以下主要发现。致病性大肠埃希菌：(1)根据O157 Sakai基因序列，建立了OA基因芯片和全基因组PCR扫描方法。(2)利用这两种方法对O157和非O157肠出血性大肠杆菌(EHEC)进行了大规模的基因组比较，发现O157菌株之间存在着显著的基因组多样性，前驱体和IS元件的变异是产生这种基因组多样性的主要因素。此外，我们还发现，非O157 EHEC菌株含有大量O157中没有的DNA。(3)我们发现RcsCDB双组分调控系统和碳酸氢盐敏感系统控制着毒力基因的表达，并发现了新的调控因子grvA和pch，它们参与了…的调控。更多的离子系统通过表达谱分析使用微阵列进行分析。这为了解致病性大肠杆菌的毒力基因表达系统如何整合到大肠杆菌的内在调控网络中提供了第一条线索。(4)利用蛋白质组学方法，我们发现了O157.2的III型分泌系统(TTSS)的许多新的效应因子。产气荚膜梭菌：(1)测定了13号菌株的基因组序列。(2)利用基于其基因组序列构建的微阵列，我们鉴定了141个受病毒/S双组分调控系统或病毒/S-VR-RNA系统调控的基因。它们不仅包括毒力基因，而且还包括许多能量产生和代谢基因，表明寄主组织中的毒力和生长基因受到VERR/S-VR-RNAs系统的协调调控。(3)通过对病毒结合序列的搜索，我们鉴定出两个新的调控RNAs。副溶血性弧菌：(1)测定了RIMD2210633菌株的基因组序列。(2)我们在其基因组上鉴定了两个TTSS1和TTSS2，发现TTSS1参与细胞毒性，TTSS2参与致泻。(3)我们为每个TTS识别了几个效应器，发现S这两个TTS表现出明显的效应器特异性。较少

In this research, we performed a comprehensive analysis of the pathogenesis and genomic diversity of three important pathogenic bacteria based on their genome sequences, and obtained followings major findings.1. Pathogenic Escherichia coli:(1) Based on the O157 Sakai sequence, we developed ○a microarray and the whole genome PCR scanning method. (2) By using these two methods, we performed a large-scale genomic comparison of O157 and non-O157 enterohemorrhagic E. coli (EHEC) strains, and revealed that there exits a remarkable genomic diversity among O157 strains, and that variation of prophages and IS elements are major factors to generate this genomic diversity. Furthermore, we revealed that non-O157 EHEC strains contain a large amount of DNAs that are not present in O157. (3) We found that the RcsCDB two component regulatory system and the bicarbonate-sensing system control the virulence gene expression, and discovered novel regulators, GrvA and Pch, that are involved in these regulat … More ion systems by expression profiling anakyses using the microarray. This provided the first clue to understand how the virulence gene expression systems of pathogenic E. coli are incorporated into the intrinsic regulatory network of E. coli. (4) By employing a proteomic approach, we discovered many new effectors for the type III secretion system (TTSS) of O157.2. Clostridium perfringen :(1) The genome sequence of strain 13 was determined. (2) By using the microarray constructed based on its genome sequence, we identified 141 genes that are controlled by the VirR/S two component regulatory system or the VirR/S-VR-RNA system. They included not only virulence genes but also many genes for energy production and metabolism, indicating that genes for virulence and growth in host tissues are coordinately regulated by the VirR/S-VR-RNA system. (3) By searching the VirR-binding sequences, we identified two novel regulatory RNAs.3. Vibrio parahaemolyticus :(1) The genome sequence of strain RIMD2210633 was determined. (2) We identified two TTSSs (TTSS1 and TTSS2) on its genome, and found that TTSS1 is involved in cell toxicity and TTSS2 in diarrheagenicity. (3) We identified several effectors for each TTSS, and found that the two TTSS s exhibit distinct effector-specificities. Less