Peptidoglycan Fragment Library to Investigate Innate Immune Responses

项目摘要 细菌细胞用肽聚糖（PG）细胞壁包围自己，这是一种抵抗细菌生长的基本结构。 渗透压和其他环境损害的变化。本提案的目标是开发一个PG 片段文库，其捕获天然多样性以促进适当的先天性和适应性免疫 生物学研究。PG片段被先天免疫系统用于正确识别和响应 细菌的存在。我们假设PG多样性天然存在于众多的细菌中， 物种是产生正确的免疫反应宿主防御必不可少的。研究这些重要的 PG片段由于缺乏可重复的高纯度化合物而受到阻碍。目前，研究人员 仅限于少数碳水化合物探针，如MDP，甚至更少的较大片段。我们建议 功能化三个碳水化合物核心：单糖，二糖和肽二聚体，选择氨基 在多种细菌物种中高度代表的酸。合成工作流程是模块化的， 建立了我们在生产高纯度PG片段方面的专业知识，并允许用化学修饰 在文库成员上的多个精确点处的生物探针。这种类型的大型PG片段库没有 以前生产过。为了克服这一挑战，我们建议使用所有三种中间体 碳水化合物核心我们的目标是使用这个库来询问先天免疫反应引起的， 巨噬细胞在目标一中，将进行大规模的模块化合成工作，以生产>400 会员图书馆。对于目的二，二糖和肽连接的二聚体家族成员将用于 一个公正的全基因组转录组分析，以解开基因表达的签名，定义了 对骨髓源性巨噬细胞中PG类的反应。我们将合成化学生物学 用于研究受体和信号伴侣的探针。目的三将探讨先天免疫反应， 通过生产PG-微阵列的PG。该阵列将在多个方向上固定PG导数 允许潜在受体扫过化学空间。这些阵列将用于评估 PG识别中指示的多种先天免疫受体的底物结合偏好。此库 将准确捕获PG片段的多样性，为拟议的免疫学 微生物和免疫学群落的分析和新工具。

PROJECT SUMMARY Bacterial cells surround themselves with a peptidoglycan (PG) cell wall, an essential structure that resists changes in osmotic pressure and other environmental insults. The goal of this proposal is to develop a PG fragment library that captures the natural diversity to facilitate the proper innate and adaptive immunity biological studies. PG fragments are used by the innate immune system to correctly recognize and respond to the presence of bacteria. We hypothesize that PG diversity naturally present across the multitude of bacterial species is essential for generating the correct immune response for host defense. Study of these important PG fragments has been hampered by the lack of reproducible, high purity compounds. Currently, researchers are limited to few carbohydrate probes, such as MDP, and even fewer larger fragments. We propose to functionalize three carbohydrate cores: monosaccharide, disaccharide and peptide dimers, with select amino acids which are highly represented across a variety of bacterial species. The synthetic workflow is modular, builds off our expertise in producing highly pure PG fragments and permits for modification with chemical biology probes at multiple pinpoints on the library members. A large PG fragment library of this type has not been produced before. To overcome this challenge we propose to use common intermediates for all three carbohydrate cores. We aim to use this library to interrogate innate immune responses elicited in macrophages. In Aim One, a large-scale, modular synthetic effort will be undertaken to produce the >400 member library. For Aim Two the disaccharide and peptide linked dimer family members will be employed in an unbiased genome wide transcriptome analysis to unravel gene expression signatures that define the responses to PG classes in bone marrow derived macrophages. We will synthesize the chemical biology probes to investigate receptors and signaling partners. Aim Three will probe the innate immune response of the PG through the production of a PG-microarray. This array will fix the PG derivatives in multiple orientations permitting the sweeping of potential receptors across chemical space. The arrays will be used to assess the substrate binding preferences of a variety of innate immune receptors indicated in PG recognition. This library will accurately capture the PG fragment diversity, providing powerful probes for the proposed immunological assays and new tools for the microbial and immunological communities.