Choline phosphotransferase-dependent phospholipid synthesis in Treponema

密螺旋体中胆碱磷酸转移酶依赖性磷脂合成

• 批准号: 7509591
• 负责人: J CHRISTOPHER FENNO
• 金额: $ 26.6万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-17 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7509591
• 关键词: 1,2-diacylglycerol; Address; Anabolism; Antibiotic Resistance; Area; Cellular Structures; Choline; Chronic; Communicable Diseases; Cytidine Diphosphate Choline; DNA; Development; Diglycerides; Elements; Environment; Enzymes; Ethanolamines; Eukaryota; Eukaryotic Cell; Event; Facility Construction Funding Category; Future; Genes; Genetic; Genome; Glycoconjugates; Homologous Gene; Horizontal Gene Transfer; Human; Hybrids; Knowledge; Laboratories; Lecithin; Life Style; Membrane; Membrane Biology; Microbe; Mitochondrial Carnitine Palmitoyltransferase Pathway; Order Spirochaetales; Organism; Pathway interactions; Phosphatidylethanolamine; Phospholipids; Phosphorylcholine; Phosphotransferase Gene; Phosphotransferases; Positioning Attribute; Process; Public Health; Range; Regulation; Role; Saccharomyces cerevisiae; Testing; Therapeutic Agents; Tissues; Treponema; Treponema denticola; Treponema pallidum; Up-Regulation; Virulence; base; ethanolamine; insight; mutant; novel; novel therapeutics; pathogen; phosphatidylethanolamine; uptake

DESCRIPTION (provided by applicant): The unique CDP-choline pathway for phosphatidylcholine (PtdCho) biosynthesis present in spirochetes of the genus Treponema is likely both a consequence of and a contributor to the commensal/pathogenic lifestyles of these organisms, reflecting their coevolution with eukaryotic hosts. We hypothesize that the final enzyme step in T. denticola PtdCho synthesis (1,2- diacylglycerol choline phosphotransferase [CPT]) is encoded by TDE0021, a gene of apparent eukaryotic origin. In many eukaryotes, this enzyme also has 1,2-diacylglycerol ethanolamine phosphotransferase (EPT) activity required for phosphatidylethanolamine (PtdEtn) synthesis. In T. denticola, PtdEtn (synthesized by an as-yet unidentified pathway) is upregulated when the first step in PtdCho synthesis is blocked. We hypothesize that T. denticola TDE0021 encodes CPT activity and may also have EPT activity, thus making it the key enzyme in phospholipid synthesis and an attractive target for development of specific anti-Treponema agents against a range of mucosal and venereal treponematoses. This application addresses the following areas: Aim 1: To characterize the CPT activity of T. denticola required for synthesis of PtdCho. We will determine if T. denticola TDE0021 encodes CPT activity by (A) construction and characterization of an isogenic TDE0021 mutant and (B) complementation of a Saccharomyces cerevisiae CPT/EPT mutant with T. denticola TDE0021 DNA. Aim 2: To characterize synthesis and expression of PtdEtn in T. denticola. We will (A) identify and characterize the T. denticola PtdEtn synthesis pathway, and (B) characterize the mechanism(s) responsible for increased levels of PtdEtn in a defined PtdCho-deficient T. denticola mutant. Upon completion of the two Aims of this project, we will have made significant progress toward understanding the genetic components and mechanisms of the unique phospholipid synthesis pathway in the genus Treponema, which includes both mucosal and venereal pathogens. The knowledge gained will significantly enhance understanding of spirochete membrane biology, will provide a basis for continued studies of the role of the phospholipid environment on microbe-host interactions, and may provide the basis for development of novel therapeutic agents. PUBLIC HEALTH RELEVANCE: This project will characterize genetic components and mechanisms comprising the unique phospholipid synthesis pathways in the genus Treponema, which includes both mucosal and venereal pathogens. This will contribute to understanding of the role of the membrane phospholipid environment on microbe-host interactions, and may provide a basis for development of novel therapeutic agents.

描述（由申请人提供）：磷脂酰胆碱（PTDCHO）生物合成的独特CDP-胆碱途径存在于Treponema属的螺旋体中，这可能既可能是这些生物体的共同/病原体生活方式的结果，也是这些生物的共识，反映了它们与Eukary宿主的同步。我们假设T. denticola ptdcho合成（1,2-二酰甘油胆碱磷酸转移酶[CPT]）的最终酶步骤由TDE0021编码，TDE0021是一个明显的真核生物原状的基因。在许多真核生物中，该酶也具有1,2-二酰基甘油乙醇胺磷酸转移酶（EPT）的活性，用于磷脂酰乙醇胺（PTDETN）合成。在T. denticola中，当Ptdcho合成中的第一步被阻止时，PTDETN（由尚未确定的途径合成）被上调。我们假设T. denticola tde0021编码CPT活性，并且可能具有EPT活性，从而使其成为磷脂合成中的关键酶，也是针对一系列粘膜和静脉内treponabes范围开发特定抗treponema剂的有吸引力的靶标。该应用程序解决了以下领域：目标1：表征合成PTDCHO所需的T. denticola的CPT活动。我们将通过（a）构造和表征同生TDE0021突变体的构建和表征和（b）抗糖酵母CPT/EPT突变体与T. denticola tde0021 DNA的含量互补来确定（a）牙本质TDE0021是否编码CPT活性。目的2：表征牙霉菌中ptdetn的合成和表达。我们将（a）识别和表征牙霉菌Ptdetn合成途径，（b）表征了负责在定义的ptdcho缺乏的T. denticola突变体中负责PTDETN水平升高的机制。该项目的两个目标完成后，我们将在理解treponema属的独特磷脂合成途径的遗传成分和机制方面取得重大进展，其中包括粘膜和性病病原体。获得的知识将显着增强对螺旋体膜生物学的理解，将为继续研究磷脂环境在微生物宿主相互作用中的作用提供基础，并可能为新型治疗剂的发展提供基础。公共卫生相关性：该项目将表征遗传成分和机制，其中包括Treponema属中独特的磷脂合成途径，其中包括粘膜和性病病原体。这将有助于理解膜磷脂环境在微生物宿主相互作用中的作用，并可能为新型治疗剂的发展提供基础。