Biogenesis of lipoarabinomannan in mycobacteria

分枝杆菌中阿拉伯脂甘露聚糖的生物合成

基本信息

批准号：
7564697
负责人：
Mary Jackson
金额：
$ 33.61万
依托单位：
COLORADO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-05-01 至 2010-06-14
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7564697
关键词：
1,2-diacylglycerol Abbreviations Actinobacteria class Actinomyces Acylation Acyltransferase Adjuvant Affect Antibodies Antigen-Presenting Cells Antitubercular Agents Arabinose Attenuated Vaccines Bacteria Binding Biochemical Biochemistry Biochemistry and Cellular Biology Biogenesis Bioinformatics Biological Biological Assay Blast Cell C-Type Lectins CD209 gene Candidate Disease Gene Capillary Electrophoresis Cell model Cells Chemistry Classification Complex Corynebacterium Dendritic Cells Development Digestion Diglycerides Disease Drug Formulations Electrospray Ionization Enzymes Escherichia coli Family Fatty Acids Future Gel Genes Genetic Genome Genomics Genus Mycobacterium Glycerol Glycolipids Goals Growth Hydroxyl Radical Inositol Insertional Mutagenesis Investigation Knowledge Laboratories Lead Leprosy Libraries Ligands Lymphocyte antigen CD50 Mannose Mannosides Mannosyltransferases Mass Spectrum Analysis Measurement Measures Membrane Transport Proteins Methods Mono-S Monoclonal Antibodies Mycobacterium tuberculosis Nocardia Nomenclature Open Reading Frames Pathway interactions Periodic acid Schiff stain method Phagocytes Phosphatidylinositols Polyacrylamide Gel Electrophoresis Polymerase Chain Reaction Positioning Attribute Preparation Principal Investigator Property Proteins Proteomics Pyrenes Research Personnel Rhodococcus Screening procedure Silver Sodium Dodecyl Sulfate Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization Staining method Stains Streptomyces Structure Structure-Activity Relationship Techniques Testing Thin Layer Chromatography Time Trifluoroacetic Acid Tuberculosis Two-Dimensional Gel Electrophoresis Vaccines Work acyl group analytical tool arabinomannan base cell envelope comparative deoxycholate enzyme pathway genetic manipulation genome sequencing glycosyltransferase homologous recombination lipoarabinomannan lipomannan macrophage man mannose receptor mutant mycobacterial novel novel vaccines phosphatidylinositol mannoside programs sugar nucleotide three dimensional structure tuberculosis drugs user-friendly

项目摘要

DESCRIPTION (provided by applicant): Phosphatidylinositol mannosides (PIM) and their multiglycosylated counterparts, lipomannan (LM) and lipoarabinomannan (LAM) are complex glycolipids/ lipoglycans that are found in the envelopes of all mycobacterial species. They are important immunomodulatory molecules in the course of tuberculosis and leprosy as well as key ligands promoting the entry of mycobacteria into phagocytic and non-phagocytic cells. Although much progress has been made over the last 15 years in deciphering the structures and structure-function relationships of these molecules, little is known about their biogenesis. The elucidation of their biosynthetic pathways, in addition to providing fundamental knowledge about the biochemistry of Mycobacterium tuberculosis, would lead to the discovery of essential enzymes that could represent crucial targets for novel anti-tuberculosis drugs. The availability of defined M. tuberculosis and M. bovis BCG mutants deficient in some aspects of PIM/ LM and LAM synthesis would also enable a precise measurement of the contribution of these molecules to the immunopathogenesis of tuberculosis and suggest new vaccine strategies against this disease. We propose to exploit the recent knowledge of the structures of LAM-like molecules produced by actinomycetes together with the availability of a growing number of genome sequences of lipoglycan-producing actinomycetes to perform genome comparison studies, identify glycosyltransferases involved in the biogenesis of PIM, LM and LAM and construct lipoglycan-deficient mutants of mycobacteria. Using the CS- 35 anti-LAM monoclonal antibody and other antibodies that we have developed, we also propose to screen transposon mutant libraries of M. tuberculosis, M. bovis BCG, and M. smegmatis for mutants defective in some aspects of LAM synthesis. Mutants will be biochemically characterized using conventional methods and novel analytical tools, cell-free assays will be developed for the newly identified biosynthetic enzymes and the three-dimensional structure of these proteins will be determined. Finally, the interactions of PIM/ LM/ LAM mutants with host cells and their immunomodulatory properties will be investigated.

描述（由申请人提供）：磷脂酰肌醇甘露糖苷（PIM）及其多糖基化对应物、脂甘露聚糖（LM）和脂阿拉伯甘露聚糖（LAM）是复杂的糖脂/脂聚糖，存在于所有分枝杆菌物种的包膜中。它们是结核病和麻风病过程中重要的免疫调节分子，也是促进分枝杆菌进入吞噬细胞和非吞噬细胞的关键配体。尽管过去 15 年在破译这些分子的结构和结构-功能关系方面取得了很大进展，但人们对它们的生物发生却知之甚少。阐明它们的生物合成途径，除了提供有关结核分枝杆菌生物化学的基础知识之外，还将导致发现可能代表新型抗结核药物关键靶点的必需酶。确定的结核分枝杆菌和牛分枝杆菌 BCG 突变体（在 PIM/LM 和 LAM 合成的某些方面存在缺陷）的可用性也将能够精确测量这些分子对结核病免疫发病机制的贡献，并提出针对该疾病的新疫苗策略。我们建议利用最近对放线菌产生的 LAM 样分子结构的了解以及越来越多的产生脂聚糖的放线菌基因组序列的可用性来进行基因组比较研究，鉴定参与 PIM、LM 生物发生的糖基转移酶和 LAM 并构建脂聚糖缺陷型分枝杆菌突变体。使用CS-35抗LAM单克隆抗体和我们开发的其他抗体，我们还建议筛选结核分枝杆菌、牛分枝杆菌BCG和耻垢分枝杆菌的转座子突变体库，以寻找在LAM合成的某些方面存在缺陷的突变体。将使用常规方法和新颖的分析工具对突变体进行生化表征，将为新鉴定的生物合成酶开发无细胞测定法，并确定这些蛋白质的三维结构。最后，将研究 PIM/LM/LAM 突变体与宿主细胞的相互作用及其免疫调节特性。