Structural characterization of MCE mediated lipid transport across the Mycobacterial cell envelope

MCE 介导的脂质跨分枝杆菌细胞包膜转运的结构表征

• 批准号: 10427285
• 负责人: Casey Vieni
• 金额: $ 3.08万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10427285
• 关键词: Actinobacteria class; Adopted; Antibiotics; Architecture; Bacteria; Binding; Binding Sites; Biochemical; Biochemistry; Biological Assay; Biological Models; Cause of Death; Cell membrane; Cell surface; Cells; Cholesterol; Communicable Diseases; Complement; Complex; Cryoelectron Microscopy; Crystallization; Cytoplasm; DNA; DNA Binding; DNA Sequence; Drug Delivery Systems; Drug resistance; Environment; Escherichia coli; Gene Cluster; Genes; Genetic; Genetic Transcription; Genome; Genus Mycobacterium; Glycolipids; Hydrophobicity; Immune response; Knock-out; Lead; Life Cycle Stages; Light; Lipids; Maintenance; Mammalian Cell; Maps; Mediating; Membrane; Molecular; Movement; Mutation; Mutation Analysis; Mycobacterium smegmatis; Mycobacterium tuberculosis; Mycobacterium tuberculosis complex; Mycolic Acid; Nutrient; Operon; Organism; Pathogenicity; Phenotype; Play; Protein Family; Proteins; Regulation; Resources; Role; Specificity; Structure; Suggestion; System; Testing; Tuberculosis; Virulence; Virulence Factors; Work; antimicrobial; cell envelope; design; differential expression; improved; insight; lipid transport; mutant; mycobacterial; new therapeutic target; novel therapeutics; protein complex; rational design; resistant strain; response; structural biology; sulfolipids; tuberculosis treatment; uptake

PROJECT SUMMARY / ABSTRACT: The cell envelope of Mycobacterium tuberculosis (Mtb) serves an important role as protection against common antimicrobials and host cell defenses, but also a barrier through which Mtb must transport host derived nutrients. The MCE protein family (originally implicated in Mammalian Cell Entry) is nearly ubiquitous in double-membraned bacteria, and MCE proteins are now believed to act as transporters that facilitate lipid movement between the inner and outer membranes. While Mtb MCE proteins are critical for virulence, their mechanism in Mtb remains unclear. Due to Mtb’s distinct cell envelope Mtb MCE proteins likely adopt a unique architecture to mediate transport. In addition, throughout the course of Mtb infection MCE transporters are believed to be differentially expressed by MCE transcriptional regulators (MceRs). This suggests that environmental sensing in Mycobacteria in turn alters transcription of the mce operons. Using structural biology, biochemistry, and genetic complementation assays, I will provide the first glimpse into the architecture of Mtb Mce protein systems and elucidate how MceRs interact with their operator sequences at the molecular level to regulate mce operons. To do so I propose the following aims: (Aim 1) structure determination of the Mce4 lipid transport system from Mycobacterium smegmatis and (Aim 2) structural characterization and DNA-binding specificity of MceRs. My work will provide the first glimpse at the architecture of the M. smegmatis Mce4 transporter system, as well as the molecular mechanisms of MceR mediated mce operon regulation, which may shed light on the mechanisms of cell envelope maintenance in Mtb and provide a novel target for therapeutics.

项目摘要/摘要： 结核分枝杆菌 (Mtb) 的细胞包膜在预防结核病方面发挥着重要作用 常见的抗菌药物和宿主细胞防御，也是结核分枝杆菌运输宿主必须通过的屏障 MCE 蛋白家族（最初与哺乳动物细胞进入有关）几乎无处不在。 双膜细菌和 MCE 蛋白现在被认为可以充当促进脂质转运的转运蛋白 虽然 Mtb MCE 蛋白对于毒力至关重要，但它们的内膜和外膜之间的运动。 由于 Mtb 独特的细胞包膜，Mtb MCE 可能采用一种独特的蛋白质。 此外，在 Mtb 感染的整个过程中，MCE 转运蛋白都是介导转运的。 据信 MCE 转录调节因子 (MceR) 差异表达。 利用结构生物学，分枝杆菌中的环境传感反过来改变 mce 操纵子的转录。 生物化学和基因互补测定，我将提供对 Mtb 结构的第一眼了解 Mce 蛋白质系统并阐明 MceR 如何在分子水平上与其操纵子序列相互作用，以 为此，我提出以下目标：（目标 1）Mce4 脂质的结构测定。 来自耻垢分枝杆菌的转运系统和（目标 2）结构表征和 DNA 结合 我的工作将首次展示耻垢分枝杆菌 Mce4 的结构。 转运系统，以及 MceR 介导的 mce 操纵子调节的分子机制， 可能揭示结核分枝杆菌细胞包膜维持机制，并为结核分枝杆菌提供新的靶点 疗法。