Rewiring networks for a pathogenic lifestyle

重新连接网络以适应致病的生活方式

基本信息

批准号：
10893669
负责人：
MICHELLE DZIEJMAN
金额：
$ 60.99万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10893669
关键词：
Address Africa Asia Attenuated Bacteria Bile fluid Binding Biochemical Cholera Cholera Toxin Chromosomes Clinical Country Crowding Cues DNA DNA Binding Domain Data Developed Countries Developing Countries Diarrhea Disasters Disease Environment Epidemic Event Evolution Family Gene Expression Gene Expression Regulation Genes Genetic Genetic Transcription Genome Genomics Genotype Global Warming Goals Haiti Horizontal Gene Transfer In Vitro Infection Infrastructure Integral Membrane Protein Laboratories Life Style Mediating Membrane Microbial Biofilms Modeling Modernization Molecular Morbidity - disease rate Oceans Organism Pathogenesis Pathogenicity Pathogenicity Island Phenotype Physiological Pilum Process Production Property Proteins Public Health Regulation Regulon Reporting Role Signal Transduction South America Southeastern Asia Specificity Stimulus Surface Syria System Testing Tissues Toxin Trans-Activators Transcription Coactivator Type III Secretion System Pathway Ukraine United States Vibrio cholerae Virulence Virulence Factors War Water burden of illness cell motility cis acting element clinical sequencing clinically relevant diarrheal disease drinking water experience experimental study gene repression genetic regulatory protein gut colonization in vivo pathogen pathogenic bacteria programs protein protein interaction response trait transcriptome virulence gene waterborne pathogen

Address Africa Asia Attenuated Bacteria Bile fluid Binding Biochemical Cholera Cholera Toxin Chromosomes Clinical Country Crowding Cues DNA DNA Binding Domain Data Developed Countries Developing Countries Diarrhea Disasters Disease Environment Epidemic Event Evolution Family Gene Expression Gene Expression Regulation Genes Genetic Genetic Transcription Genome Genomics Genotype Global Warming Goals Haiti Horizontal Gene Transfer In Vitro Infection Infrastructure Integral Membrane Protein Laboratories Life Style Mediating Membrane Microbial Biofilms Modeling Modernization Molecular Morbidity - disease rate Oceans Organism Pathogenesis Pathogenicity Pathogenicity Island Phenotype Physiological Pilum Process Production Property Proteins Public Health Regulation Regulon Reporting Role Signal Transduction South America Southeastern Asia Specificity Stimulus Surface Syria System Testing Tissues Toxin Trans-Activators Transcription Coactivator Type III Secretion System Pathway Ukraine United States Vibrio cholerae Virulence Virulence Factors War Water burden of illness cell motility cis acting element clinical sequencing clinically relevant diarrheal disease drinking water experience experimental study gene repression genetic regulatory protein gut colonization in vivo pathogen pathogenic bacteria programs protein protein interaction response trait transcriptome virulence gene waterborne pathogen

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项目摘要

Project Summary Vibrio cholerae causes the severe diarrheal disease cholera that is endemic in much of Asia, Africa, and South America, and has recently reemerged in Haiti, Syria, and Ukraine. The species is highly diverse, although only O1 or O139 serogroup strains cause epidemic disease. However, increasing sporadic disease has been reported globally, and is caused by strains belonging to non-O1/non-O139 serogroups that present a public health threat both in developed and industrialized nations, including the United States. Unlike pathogenic O1 and O139 strains, the vast majority of pathogenic non-O1/non-O139 strains do not carry the well characterized virulence factors for colonization (TCP) and toxin production (CT), and the virulence mechanisms used by these strains are not well understood. Our study of pathogenic non-O1/non-O139 serogroup strains began with genomic sequencing of the clinically isolated O39 serogroup strain, AM-19226, which revealed a Type Three Secretion System (T3SS) that is conserved among other V. cholerae isolates. Like TCP and CT, the T3SS is acquired by horizontal gene transfer (HGT), and integrated into the ancestral chromosome. Our subsequent experiments identified two membrane localized transcriptional activators (MLTAs) encoded within the T3SS genomic pathogenicity island (PAI), which are essential for T3SS function in vivo and in vitro. We also found that ToxR, an ancestral MLTA required for TCP and CT expression, is important for T3SS regulation. ToxR is encoded by all strains of V. cholerae where it regulates core chromosomal functions, and is well-studied as an MLTA that cross-regulates PAI and ancestral gene expression. Interestingly, we found that the T3SS encoded MLTAs influence ancestral gene expression and phenotypes such as motility and biofilm formation. We hypothesize that in order to survive in aquatic environments and also cause disease, T3SS-positive V. cholerae must integrate virulence gene regulation with transcriptional circuits outside of the PAI, leveraging the activities of both ancestral and newly acquired, PAI encoded transcriptional regulatory factors. We propose to use complementary genetic and biochemical approaches to identify and characterize the mechanisms used by T3SS PAIs to coordinate motility, biofilm formation, and T3SS gene expression in response to environmental cues. Initial studies will define the regulons for T3SS MLTAs, and the conditions promoting regulation. We will investigate protein-protein interactions and MLTA transcriptional domain sequence specificity. Initial studies will focus on VttRA as the protein at the top of the regulatory hierarchy. Our overall goal is to discover how PAI encoded MLTA activity regulates virulence phenotypes and ancestral physiological traits that are necessary to maintain dual lifestyles of newly evolved pathogens.

项目摘要弧菌霍乱引起严重的腹泻病霍乱，在亚洲，非洲和南部的大部分地区是地方性的美国，最近在海地，叙利亚和乌克兰重新出现。该物种高度多样 O1或O139血清群菌株引起流行病。但是，偶发性疾病的增加一直是全球报告，是由属于非O1/non-O139血清群的菌株引起的包括美国在内的发达国家和工业化国家中的健康威胁。与致病性O1不同和O139菌株，绝大多数致病性非O1/non-O139菌株都不具有良好的特征定植（TCP）和毒素产生（CT）的毒力因子以及这些使用的毒力机制菌株不太了解。我们对致病性非O1/非O139血清群菌株的研究始于临床分离的O39血清群菌株AM-19226的基因组测序，该菌株揭示了三型分泌系统（T3SS）在其他V.霍乱分离株中保守。像TCP和CT一样，T3SS是通过水平基因转移（HGT）获取，并整合到祖先染色体中。我们随后的实验确定了两个膜局部转录激活剂（MLTA），该激活剂（MLTA）在T3SS中编码基因组致病岛（PAI），这对于T3SS在体内和体外的功能至关重要。我们还发现 TOXR是TCP和CT表达所需的祖先MLTA，对于T3SS调节很重要。 Toxr是由霍乱甲状腺菌的所有菌株编码，在该菌株中调节核心染色体功能，并被充分研究为跨调节PAI和祖先基因表达的MLTA。有趣的是，我们发现T3SS编码 MLTA会影响祖先基因表达和表型，例如运动和生物膜形成。我们假设为了在水生环境中生存并引起疾病，T3SS阳性V.霍乱必须将毒力基因调节与PAI之外的转录电路整合，以利用活动 PAI编码的转录调节因素中的祖先和新获得的。我们建议使用补充遗传和生化方法，以识别和表征T3SS使用的机制 PAIS以响应环境线索来协调运动性，生物膜形成和T3SS基因表达。初步研究将定义T3SS MLTA的规范，以及促进调节的条件。我们将研究蛋白质 - 蛋白质相互作用和MLTA转录域序列特异性。最初的研究将专注于VTTRA作为调节层次结构顶部的蛋白质。我们的总体目标是发现Pai 编码的MLTA活性调节毒力表型和祖先的生理特征是必要的保持新进化的病原体的双重生活方式。