Regulatory Circuits Controlling Development of Dormant Microbial Cysts

控制休眠微生物囊肿发育的调节电路

基本信息

批准号：
8215581
负责人：
CARL Eugene BAUER
金额：
$ 25.36万
依托单位：
TRUSTEES OF INDIANA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-02-01 至 2016-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8215581
关键词：
Address Animal Model Antibiotics Azospirillum Azospirillum brasilense Bacteria Binding Biochemical Biological Assay Biological Models Burkholderia mallei Caring Catalytic Domain Cell Line Cells ChIP-seq Code Complement Complex Consensus Sequence Control Locus Cyclic AMP Cyclic GMP Cyst DNA Binding Data Delftia acidovorans Desiccation Development Enzymes Escherichia coli Eukaryota Excretory function Gene Expression Gene Expression Profile Genes Genetic Genetic Transcription Goals Gram-Negative Bacteria Growth Inhibitors Guanylate Cyclase Homologous Gene Hybrids In Vitro Individual Interphase Cell Light Measures Modeling Molecular Genetics Morphogenesis Muscle Contraction Mutation Nitrogen Pathway interactions Physiology Plants Platelet aggregation Production Proteobacteria RNA Regulation Regulon Resistance Rest Rhizobium leguminosarum Rhodospirillum centenum Signal Transduction Signal Transduction Pathway Sinorhizobium Sinorhizobium fredii Sinorhizobium meliloti Starvation Stress Structure Techniques Technology Testing Time Variant Vision X-Ray Crystallography bacterial cyst cGMP production cell type genetic analysis genome sequencing genome-wide in vivo microbial mutant novel pathogen protein-histidine kinase reconstitution response transcription factor yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): This proposal is centered on genetic and biochemical characterization of regulatory factors that control development of metabolically quiescent cysts in gram-negative bacteria. Numerous beneficial bacteria that fix nitrogen for plants, as well as harmful bacterial pathogens, are capable of synthesizing cysts. Cysts are metabolically dormant resting cells that are extremely resistant to desiccation as well as to growth inhibitors such as to antibiotics. This study analyzes cyst formation in the gram-negative model organism R. centenum for which numerous cyst developmental regulatory mutants have been isolated. One class of mutants dramatically overproduces cysts while a second class of mutants dramatically inhibits cyst formation. Molecular genetic analysis of mutant cell lines led to a surprising discovery that regulation of cyst formation involved production and excretion of cGMP. cGMP is a well known messenger in eukaryotes where it is involved in vision, muscle contraction, platelet aggregation, and development. However, its involvement in bacteria has until now been quite controversial. Our recent definitive studies have unequivocally demonstrated the involvement of cGMP in R. centenum cyst development and has implicated cGMP production in many other important bacterial species such as Azospirillum brasilense, Rhizobium leguminosarum, Mesorhizobium loti, Sinorhizobium medicae, Sinorhizobium meliloti, Sinorhizobium fredii, Delftia acidovorans (Comamonas acidovorans), Burkholderia mallei (Pseudomonas mallei)). Biochemical characterization of cGMP production, and its involvement in bacterial signal transduction, is a major goal of this proposal. We have also isolated numerous additional cyst developmental regulatory mutations that contain genetic disruptions in a variety of bacterial signal transduction components and in various transcription factors. Changes in genome wide gene expression will be undertaken with each of these mutants cell lines in order to develop detailed models of the regulatory circuits that are involved in controlling bacterial cyst formation. PUBLIC HEALTH RELEVANCE: This is a study of how bacteria synthesize dormant non-replicating resting cysts. Cyst cells care capable of remaining alive without replication for many decades and are resistant to drying and to growth inhibitors such as to antibiotics. Our study will shed light on how cells control the formation of cysts with a long term goal of controlling cyst formation.

描述（由申请人提供）：该建议集中于控制革兰氏阴性细菌中代谢静止囊肿的调节因素的遗传和生化表征。固定植物的氮以及有害细菌病原体的许多有益细菌能够合成囊肿。囊肿是代谢性休眠的静息细胞，对干燥以及抗生素等生长抑制剂具有极大的抗性。这项研究分析了革兰氏阴性模型有机体中的囊肿形成，其中已分离出许多囊肿发育调节突变体。一类突变体极大地产生了囊肿，而第二类突变体则极大地抑制了囊肿的形成。突变细胞系的分子遗传分析导致令人惊讶的发现，调节囊肿的形成涉及CGMP的产生和排泄。 CGMP是真核生物中众所周知的使者，它参与视觉，肌肉收缩，血小板聚集和发育。但是，到目前为止，其参与细菌的参与一直存在争议。 Our recent definitive studies have unequivocally demonstrated the involvement of cGMP in R. centenum cyst development and has implicated cGMP production in many other important bacterial species such as Azospirillum brasilense, Rhizobium leguminosarum, Mesorhizobium loti, Sinorhizobium medicae, Sinorhizobium meliloti, Sinorhizobium fredii, Delftia酸沃尔群（Comamonas酸伏烷），Burkholderia Mallei（假单胞菌Mallei））。 CGMP产生的生化表征及其参与细菌信号转导，是该提案的主要目标。我们还分离了许多其他囊肿发育调节突变，这些突变包含各种细菌信号转导组件和各种转录因子中的遗传破坏。这些突变体细胞系将进行基因组广泛的基因表达的变化，以开发与控制细菌囊肿形成有关的调节回路的详细模型。公共卫生相关性：这是对细菌如何合成休眠不复制静止囊肿的研究。囊肿细胞能够保持活力数十年而无需复制，并且对干燥和抗生素等生长抑制剂具有抗性。我们的研究将阐明细胞如何控制囊肿形成的长期目标。