Intercellular Communication and Pheromone Maturation in Gram-Positive Bacteria.

革兰氏阳性细菌的细胞间通讯和信息素成熟。

• 批准号: 10153696
• 负责人: Francis Alonzo
• 金额: $ 37.7万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10153696
• 关键词: Active Sites; Affect; Amino Acid Sequence; Attenuated; Behavior; Biochemical; Biochemistry; Cell Communication; Cell membrane; Cells; Characteristics; Cleaved cell; Communicable Diseases; Communities; Competence; Congenic Strain; Cyclic Peptides; Cysteine; Data; Defect; Development; Disease; Elements; Enterococcus; Event; Family; Gene Expression; Genes; Genetic Screening; Genus staphylococcus; Goals; Gram-Positive Bacteria; Grant; Health; Infection; Infectious Skin Diseases; Knowledge; Link; Listeria; Lung infections; Mass Spectrum Analysis; Mechanics; Mediator of activation protein; Membrane; Membrane Proteins; Metal Binding Site; Metalloproteases; Microbe; Microbial Biofilms; Modeling; Mus; Mutation; N-terminal; Open Reading Frames; Pathogenesis; Pathogenicity; Peptide Biosynthesis; Peptide Hydrolases; Peptide Leader Sequences; Peptide Signal Sequences; Peptides; Periodicity; Pheromone; Process; Production; Protein Precursors; Proteins; Recombinants; Regulator Genes; Role; Signal Induction; Signal Transduction; Specificity; Staphylococcus aureus; System; Testing; Variant; Virulence; Virulence Factors; attenuation; base; genetic approach; improved; insight; intercellular communication; mutant; novel therapeutics; pathogen; protein aminoacid sequence; quorum sensing; trait

Project Summary Gram-positive bacteria process and release small peptides, or “pheromones”, that act as critical signals for the induction of adaptive traits including those involved in virulence. One class of small signaling pheromones is the cyclic auto-inducing peptide (AIP), which regulates the expression of genes that orchestrate virulence and persistence in Staphylococci, Listeria, Clostridia, and Enterococci. Defects in cyclic AIP production and signaling can compromise virulence traits of these microbes, underscoring the relevance of peptide-based signaling to health and disease. Staphylococcus aureus harbors a cyclic peptide signaling system known as the accessory gene regulatory (Agr) system. This “quorum sensing” system depends on the synthesis, processing, and export of a cyclic AIP, derived from its precursor protein, AgrD, for function. AIP signaling through Agr leads to the production of S. aureus virulence factors, whereas disruption of signaling causes significant attenuation in skin and lung infection models. Despite clear connections between Agr and S. aureus pathobiology, there exist major gaps in our knowledge of the mechanics of AIP biosynthesis. Most notably: (i) the proteins needed for peptide processing of AIP have not been elucidated; (ii) a transporter for AIP or its leader peptide has not been identified; (iii) differential processing of AIP variants has not been investigated; and (iv) conservation in cyclic peptide processing events between bacterial species is not known. In this grant, we provide data related to our discovery of a putative peptidase in S. aureus, MroQ, that we hypothesize acts directly or indirectly on Agr system components to promote the final steps in the processing and/or export of AIP. The overall goals of this grant are to interrogate the previously unknown mechanics of cyclic peptide maturation in S. aureus and provide insight into the potential conservation of function in Gram positive pathogens. Aim 1 will define how MroQ promotes AIP processing, export, or both. Aim 2 will interrogate the extent with which MroQ interacts with Agr system or other membrane components and will use biochemistry to test if MroQ directly cleaves AgrD. Aim 3 will determine the extent with which MroQ promotes activity of Agr variants both within species and among other species and identify the AgrD sequence characteristics that dictate MroQ specificity.

项目摘要 革兰氏阳性细菌过程并释放小胡椒或“信息素”，是该关键信号 诱导适应性特征，包括参与病毒的特征。一类小信号信息素是 环状自动诱导肽（AIP），该肽调节了编排病毒和的基因表达 葡萄球菌，李斯特菌，梭菌和肠球菌的持久性。循环AIP产生缺陷和 信号传导会损害这些微生物的病毒特征，从而强调基于胡椒的相关性 向健康和疾病发出信号。金黄色葡萄球菌拥有一个被称为的环状肽信号传导系统 附件基因调节（AGR）系统。这个“法定人心的灵敏度”系统取决于合成， 源自其前体蛋白Agrd的循环AIP的处理和导出。 AIP信号传导 通过AGR导致金黄色葡萄球菌病毒因子的产生，而信号的破坏原因 皮肤和肺部感染模型的大量衰减。尽管AGR和金黄色葡萄球菌之间有明确的联系 病理生物学，我们对AIP生物合成力学的了解存在主要差距。最值得注意的是：（i） 尚未阐明AIP肽加工所需的蛋白质； （ii）AIP或ITS的转运蛋白 尚未确定领导肽； （iii）尚未研究AIP变体的差异处理； （iv）尚不清楚细菌物种之间的环状肽加工事件中的保护。在这笔赠款中， 我们提供与我们在Mroq S. Aureus中发现假定肽的数据有关的数据，该数据我们假设行为 直接或间接在AGR系统组件上，以促进处理和/或出口的最终步骤 AIP。这笔赠款的总体目标是审问以前未知的循环胡椒的力学 金黄色葡萄球菌的成熟，并深入了解革兰氏阳性功能的潜在守恒 病原体。 AIM 1将定义MROQ如何促进AIP处理，出口或两者兼而有之。 AIM 2会审问 MROQ与AGR系统或其他膜组件相互作用的程度，并将使用生物化学来 测试MROQ是否直接切割Agrd。 AIM 3将确定MROQ促进AGR活性的程度 物种内部和其他物种中的变体，并确定AGRD序列特征 决定MROQ特异性。