Glycosylation as a Structural Determinant in Peptide Fibrillization

糖基化作为肽纤维化的结构决定因素

• 批准号: 10649457
• 负责人: Gregory Hudalla
• 金额: $ 37.56万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10649457
• 关键词: Architecture; Binding; Biocompatible Materials; Biological; Biological Models; Biophysics; Carbohydrate Chemistry; Carbohydrates; Cartilage; Cell surface; Data; Degenerative polyarthritis; Disease; Equilibrium; Future; Glycoproteins; Health; Human; Joints; Kinetics; Knowledge; Libraries; Lubrication; Mediating; Methods; Modification; Molecular; Morphology; Mucins; Nature; Peptides; Production; Property; Protein Glycosylation; Proteins; Research; Role; Sorting; Surface; Testing; analog; beta pleated sheet; biophysical techniques; carbohydrate analog; carbohydrate binding protein; carbohydrate receptor; cost effective; design; glycosylation; insight; lubricin; nanofiber; prevent; programs; protein folding; self assembly; structural determinants; success

Project Summary. All human cell surfaces and nearly half of all human proteins are decorated with carbohydrates (i.e., glycosylated), yet our understanding of the role of glycosylation in health and disease remains limited. Increasing evidence is establishing a central role for glycosylation as a determinant of protein folding, sorting, processing, export, and function. Advancing this understanding requires platforms to systematically study changes in protein form and function resulting from altered glycosylation, which has historically required highly specialized expertise in protein production and carbohydrate synthesis. As a practical alternative, my research program develops carbohydrate-modified peptides that self-assemble into fibrillar architectures as synthetic analogs of glycosylated proteins. The proposed research program will study how glycosylation influences peptide fibrillization as a surrogate for protein folding, and will use these insights to enable design of new biomaterials. Preliminary data supporting the proposed research demonstrate that glycosylation can facilitate hierarchical self-assembly of a synthetic b-sheet fibrillizing peptide into anisotropic networks of aligned nanofibers. These anisotropic networks resist non-specific biological interactions yet selectively recognize carbohydrate-binding proteins due to the emergent function of carbohydrates assembled into a multivalent architecture. The overarching hypothesis of the proposed research is that glycosylation influences peptide fibrillization and nanofiber function by establishing intermolecular forces that mediate specific binding interactions while preventing non-specific associations. To test this, we will first develop a method for scalable, cost-effective synthesis of a library of fibrillizing peptides modified with a broad range of carbohydrate chemistries. Then we will use this library to study the influence of glycosylation on the kinetics of peptide fibrillization and equilibrium morphology of the resultant nanofibers using various biophysical methods. Together, these studies will establish fundamental understanding of glycosylation as a structural determinant in peptide fibrillization. Finally, we will evaluate glycosylated peptide nanofibers as biomaterials that recapitulate the form and function of lubricin, a cartilage glycoprotein that provides boundary lubrication at the joint surface, which is lost during osteoarthritis progression. Although we use synthetic fibrillizing peptides as a model system, general observations made through this research program are expected to be applicable to the biophysics of natural fibrillizing peptides, and may also inform understanding of mucins and other densely glycosylated proteins. Success of this research will advance the field of supramolecular biomaterials by establishing carbohydrates as a new class of molecular motif for controlling peptide fibrillization. Ultimately, this research will support future efforts to develop biomaterials with new structural and functional properties that are desirable for biomedical applications by creating peptides modified with diverse carbohydrate chemistries found throughout nature.

项目摘要。所有人类细胞表面和所有人类蛋白的几乎一半都装饰 碳水化合物（即糖基化），但是我们对糖基化在健康和疾病中的作用的理解 仍然有限。越来越多的证据是确定糖基化作为蛋白质决定因素的核心作用 折叠，排序，处理，导出和功能。提高这种理解需要平台 系统地研究因糖基化改变而导致的蛋白质形式和功能的变化，这具有 从历史上看，在蛋白质生产和碳水化合物合成方面需要高度专业的专业知识。作为一个实用 替代方案，我的研究计划开发了自组装成纤维的碳水化合物修饰的肽 结构作为糖基化蛋白的合成类似物。拟议的研究计划将研究如何 糖基化将肽纤维化作为蛋白质折叠的替代物，并将这些见解用于 启用新生物材料的设计。支持拟议研究的初步数据表明 糖基化可以促进合成B-表纤维化肽的分层自组装到各向异性 对齐纳米纤维的网络。这些各向异性网络抵抗非特异性生物学相互作用 由于组装的碳水化合物的紧急功能，有选择地识别碳水化合物结合蛋白 进入多价体系结构。拟议研究的总体假设是糖基化 通过建立介导特异性的分子间力来影响肽纤维化和纳米纤维功能 结合相互作用，同时预防非特异性关联。为了进行测试，我们将首先开发一种方法 可扩展的，具有成本效益的合成，该库的纤维化肽库用广泛的碳水化合物修饰 化学。然后，我们将使用该库研究糖基化对肽动力学的影响 使用各种生物物理方法的纳米纤维的纤维化和平衡形态。一起， 这些研究将建立对糖基化作为肽的结构决定因素的基本理解 纤维化。最后，我们将评估糖基化的肽纳米纤维作为概括形式的生物材料 润滑剂的功能，润滑剂是一种软骨糖蛋白，可在关节表面提供边界润滑 在骨关节炎进展过程中丢失。尽管我们使用合成纤维化肽作为模型系统，但一般 预计通过该研究计划进行的观察将适用于自然的生物物理学 纤颤的肽，也可能告知人们对粘蛋白和其他密集糖基化蛋白的理解。 这项研究的成功将通过建立碳水化合物作为超分子生物材料的领域 一种用于控制肽纤维化的新的分子基序。最终，这项研究将支持未来 努力开发具有新结构和功能特性的生物材料，这些特性是生物医学是可取的 通过创建在整个自然中发现的碳水化合物化学的多种化学作用来修饰的肽。