Ca2+-binding protein EfhP mediates Ca2+ regulation of Pseudomonas aeruginosa virulence and host-pathogen interactions.

Ca2 结合蛋白 EfhP 介导 Ca2 对铜绿假单胞菌毒力和宿主-病原体相互作用的调节。

• 批准号: 9795472
• 负责人: Marianna Patrauchan
• 金额: $ 2.9万
• 依托单位: OKLAHOMA STATE UNIVERSITY STILLWATER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9795472
• 关键词: Affect; Amino Acids; Bacteria; Bacterial Infections; Binding; Binding Proteins; Calcium; Calmodulin; Clinical; Communicable Diseases; Cystic Fibrosis sputum; Development; Disease; EF Hand Motifs; Endocarditis; Ensure; Environment; Eukaryota; Genetic Transcription; Homeostasis; Implant; Infection; Innate Immune Response; Journals; Knowledge; Measures; Mediating; Modernization; Molecular; Pathway interactions; Patients; Peer Review; Physiological Processes; Play; Process; Production; Prokaryotic Cells; Proteins; Pseudomonas aeruginosa; Publications; Pulmonary Heart Disease; Regulation; Regulatory Pathway; Research; Role; Sampling; Signal Pathway; Signal Transduction; Students; Testing; Training; Virulence; Virulence Factors; antimicrobial drug; career networking; chronic infection; cystic fibrosis infection; design; graduate student; human disease; human pathogen; innovation; meetings; novel; novel therapeutics; pathogen; response; therapy development; undergraduate student; wound

Calcium (Ca2+) is one of the most important intra- and intercellular messengers in eukaryotes, where it regulates many essential processes, including innate immune responses. Therefore, abnormalities in cellular Ca2+ homeostasis have been implicated in many diseases, including pulmonary and heart diseases that are commonly associated with bacterial infections. In bacteria, Ca2+ has been shown to affect various physiological processes including virulence. However, the molecular mechanisms of this regulation are still elusive. Identification and characterization of proteins involved in Ca2+ regulatory and signalling pathways will not only provide a missing direct evidence of the signalling role of Ca2+ in prokaryotes, but more importantly, will provide a new understanding of Ca2+-regulated host-pathogen interactions triggering the development of infectious diseases. In the proposed research we will study Pseudomonas aeruginosa, a facultative human pathogen that is a leading cause of severe chronic infections in cystic fibrosis (CF), endocarditis, wound, burn, and implant patients. Earlier we showed that elevated Ca2+ enhances the production of virulence factors and infectivity in P. aeruginosa. We identified a putative Ca2+-binding protein, EfhP, which is homologous to calmodulin and contains two canonical EF-hand motifs. We hypothesize that EfhP binds Ca2+ and plays a key role in Ca2+ signaling and regulation of virulence. To test the hypotheses we will 1) measure Ca2+ binding by EfhP and identify the required amino acid residues; 2) characterize the role of EfhP Ca2+ binding in regulation of virulence factors; 3) characterize the transcriptional profile of efhP in response to Ca2+, other host-related factors, in clinical isolates and CF sputum samples; 4) identify the regulatory phosphorelay pathways triggered by EfhP Ca2+-binding; and 5) characterize the role of EfhP and Ca2+ in P. aeruginosa-host interactions. The research is innovative as it will be first to study the relationship between Ca2+-binding protein, Ca2+ signaling and Ca2+-regulated virulence in a human pathogen of extremely high importance. Understanding the molecular mechanisms by which Ca2+ regulates P. aeruginosa virulence will advance the current understanding of infectious diseases associated with Ca2+ imbalance and eventually provide novel targets for developing new antimicrobial drugs. The proposed research will be performed by teams of undergraduate and graduate students. It is designed to provide an excellent training environment for students by ensuring their involvement in modern research, their participation in scientific meetings and professional networking, and their publications in peer-reviewed journals.

钙(Ca~(2+))是真核生物细胞内和细胞间最重要的信使之一， 在那里它调节许多重要的过程，包括先天免疫反应。因此， 细胞内钙稳态的异常与许多疾病有关，包括 通常与细菌感染有关的肺病和心脏病。在……里面 细菌，钙离子已被证明影响包括毒力在内的各种生理过程。 然而，这种调控的分子机制仍然不清楚。身份识别和 对参与钙调节和信号通路的蛋白质的表征不仅将 提供了原核生物中钙离子信号作用的缺失的直接证据，但更多 重要的是，这将提供对钙离子调节的宿主-病原体相互作用的新的理解 引发传染病的发展。在拟议的研究中，我们将研究 铜绿假单胞菌，一种兼性的人类病原体，是严重 囊性纤维化(CF)、心内膜炎、伤口、烧伤和植入物患者的慢性感染。早些时候 结果表明，高浓度的钙离子可促进赤霉菌毒力因子的产生和感染力。 铜绿假单胞菌。我们鉴定了一个可能的钙结合蛋白，EfhP，它与 钙调蛋白，包含两个典型的EF-Hand基序。我们假设Efhp与钙离子结合 在Ca~(2+)信号转导和毒力调控中起关键作用。为了检验这些假设，我们将 1)测定EfhP与钙离子的结合量，确定必需的氨基酸残基；2)表征 EfhP钙结合在毒力因子调控中的作用；3)转录特性 临床分离株和CF痰中EFHP对Ca~(2+)等宿主相关因子的反应 样本；4)确定EfhP钙结合触发的调节磷酸传递途径；以及 5)研究EfhP和钙离子在铜绿假单胞菌-宿主相互作用中的作用。这项研究是 首次研究钙结合蛋白、钙离子之间的关系具有创新性 信号和钙离子调节的毒力在人类病原体中具有极高的重要性。 了解钙离子调节铜绿假单胞菌毒力的分子机制 促进当前对与钙离子失衡相关的传染病的认识 最终为开发新的抗微生物药物提供新的靶点。拟议的研究 将由本科生和研究生组成的团队表演。它旨在提供 通过确保学生参与现代研究，为学生提供良好的培训环境， 他们参加科学会议和专业网络，并在 同行评议的期刊。