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（Ca2+）是真核生物中最重要的细胞内和细胞间信使之一 它调节许多基本过程，包括先天免疫反应。所以， 细胞Ca2+稳态异常已与许多疾病有关，包括 通常与细菌感染相关的肺部和心脏病。在 细菌，Ca2+已显示出影响包括毒力在内的各种生理过程。 但是，该调节的分子机制仍然难以捉摸。识别和 参与Ca2+调节和信号通路涉及的蛋白质的表征不仅会 提供Ca2+在原核生物中的信号传导作用的直接证据，但更多 重要的是，将提供对CA2+调节的宿主 - 病原体相互作用的新理解 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，一种辅助人类病原体，是严重的主要原因 囊性纤维化（CF），心内膜炎，伤口，烧伤和植入患者的慢性感染。较早 我们表明，Ca2+升高会增强毒力因子的产生和P。 铜绿。我们确定了推定的Ca2+结合蛋白EFHP，该蛋白与 钙调蛋白，并包含两个规范的EF手基序。我们假设EFHP结合了Ca2+ 并在Ca2+信号传导和毒力调节中起关键作用。为了检验假设，我们将 1）测量EFHP的Ca2+结合，并确定所需的氨基酸残基； 2）表征 EFHP Ca2+结合在毒力因子调节中的作用； 3）特征转录 临床分离株和CF痰中的Ca2+响应其他宿主相关因素的EFHP的曲线 样品； 4）确定由EFHP CA2+结合触发的调节磷光途径；和 5）表征EFHP和Ca2+在铜绿假单胞菌 - 宿主相互作用中的作用。研究是 创新性，因为它将首先研究Ca2+结合蛋白Ca2+之间的关系 信号传导和Ca2+调节的毒力非常重要。 了解Ca2+调节铜绿假单胞菌毒力的分子机制将 促进对与CA2+不平衡相关的传染病的当前理解 最终为开发新的抗菌药物提供了新的靶标。拟议的研究 将由本科和研究生团队进行。它旨在提供 学生通过确保参与现代研究的出色培训环境， 他们参加了科学会议和专业网络，以及他们的出版物 同行评审的期刊。