Inhibition of Glycoprotein Biosynthesis in Gram-Negative Pathogens

革兰氏阴性病原体糖蛋白生物合成的抑制

• 批准号: 8420337
• 负责人: Barbara Imperiali
• 金额: $ 3.89万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-02-06 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8420337
• 关键词: Acetyl Coenzyme A; Acetyltransferase; Acids; Acinetobacter baumannii; Address; Anabolism; Anti-Bacterial Agents; Antibiotic Resistance; Antibiotics; Biological; Biological Assay; Campylobacter; Campylobacter jejuni; Cell Adhesion; Cell Wall; Cell surface; Cells; Cellular Assay; Chemicals; Chemistry; Communicable Diseases; Dependence; Development; Dose; Enzyme Inhibitor Drugs; Enzyme Inhibitors; Enzymes; Genes; Glycoconjugates; Glycoproteins; Goals; Gram-Negative Bacteria; HAT1 gene; Histones; Human; In Vitro; Inhibitory Concentration 50; Institutes; Lead; Lectin; Link; Lipopolysaccharides; Mammalian Cell; Membrane Glycoproteins; Methodology; Molecular; NIH 3T3 Cells; Neisseria gonorrhoeae; Pan Genus; Pathogenesis; Pathogenicity; Pathway interactions; Play; Procedures; Production; Prokaryotic Cells; Protein Glycosylation; Public Health; Publishing; Radioactivity; Reagent; Research; Resistance development; Role; Structure-Activity Relationship; Therapeutic Agents; Toxic effect; Transferase; Virulence; Virulence Factors; Western Blotting; Work; antimicrobial; bacillosamine; base; combat; cross reactivity; enzyme activity; glycoprotein biosynthesis; glycosylation; high throughput screening; human HAT1 protein; in vitro Assay; inhibitor/antagonist; interest; link protein; microbial; new therapeutic target; novel; novel strategies; novel therapeutics; pathogen; pathogenic bacteria; screening; small molecule; sugar; tool

DESCRIPTION (provided by applicant): It is well known that antibiotic resistance is a critical issue in the battle against microbial pathogens. Less well known is the way forward to new approaches in antibacterial therapy that address the serious consequences of resistance development. In the past decade bacterial cell surface glycoconjugates, including the lipopolysaccharide (LPS) component of the outer cell wall and cell surface N- and O-linked glycoproteins of several medically relevant Gram-negative bacteria pathogens, have been characterized in molecular detail and found to be essential for host-dependent virulence and pathogenicity. We propose to employ a high-throughput small-molecule screening strategy to identify potent and selective inhibitors of an essential step in the biosynthesis of di-N-acetylbacillosamine (diNAcBAc), which is a highly modified saccharide that features as an essential building block in the cell-surface glycoconjugates of many Gram-negative pathogens. The current studies target the discovery of small molecule inhibitors of the enzyme PglD, which is an acetyl-CoA-dependent acetyl transferase that carries out the final step in the conversion of UDP-GlcNAc into UDP-diNAcBac in the N-linked protein glycosylation pathway of the enteropathogen Campylobacter jejuni. Phenotypic studies establish that UDP-diNAcBac is an obligatory intermediate in the pathway that ultimately affords bacterial cell-surface N-linked glycoproteins that are involved in host cell adhesion, invasion and colonization. Therefore, smal-molecule inhibitors that result from these studies would be incisive chemical tools for elucidating the fundamental roles of highly modified saccharides in microbial virulence and pathogenesis. Additionally, the probes would represent novel leads in the development of new therapeutic agents and validate a new class of antibiotic target. This research addresses the central hypothesis that the biosynthetic pathways in pathogenic bacteria that lead to highly modified sugar building blocks, such as di-N-acetyl-bacillosamine, represent an "Achilles' heel" that can be exploited in the battle against infectious diseases. The general principles that we develop in these studies will be applicable to other microbial pathogens that implement prokaryote- specific N- and O-linked glycoproteins as virulence factors. If successful, the research will identify new enzyme targets and strategies in the global crisis of combating infectious diseases in the face of escalating antibiotic resistance.

描述（由申请人提供）：众所周知，抗生素耐药性是对抗微生物病原体的关键问题。不太为人所知的是，在解决耐药性发展的严重后果的抗菌治疗新方法的前进道路。在过去的十年中，细菌细胞表面糖缀合物，包括外细胞壁的脂多糖（LPS）成分和几种医学上相关的革兰氏阴性细菌病原体的细胞表面N-和o -连接糖蛋白，已经在分子细节上进行了表征，并发现对宿主依赖性毒力和致病性至关重要。我们建议采用高通量小分子筛选策略来识别二n -乙酰杆菌胺（diNAcBAc）生物合成中一个重要步骤的有效和选择性抑制剂，diNAcBAc是一种高度修饰的糖类，在许多革兰氏阴性病原体的细胞表面糖缀合物中具有重要的构建块。目前的研究目标是发现pld酶的小分子抑制剂，pld酶是一种乙酰辅酶a依赖的乙酰转移酶，在肠致病菌空肠弯曲杆菌的n -连接蛋白糖基化途径中将UDP-GlcNAc转化为UDP-diNAcBac的最后一步。表型研究证实，UDP-diNAcBac是最终提供细菌细胞表面n -连接糖蛋白的必经中间体，参与宿主细胞的粘附、侵袭和定植。因此，从这些研究中产生的小分子抑制剂将是阐明的敏锐化学工具