針對醣苷水解酶來發展及合成分子工具之研究

Synthetic Efforts toward the Development of Molecular Tools Targeting Glycosidases

呂學宸(Hsueh-Chen Lu)

指導教授 ： 吳世雄

國立臺灣大學/理學院/化學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201701971

摘要

摘要
醣苷水解酶 (glycosidases)是廣泛存在於生物體中的酵素，能催化醣苷鍵的水解反應，並在醣質代謝和維持細胞正常生理機能上扮演著重要角色。由於失調的醣苷水解酶活性與許多疾病及癌症有著密切的關係，因此以醣苷水解酶為作用對象的抑制劑之設計與合成，或探討其所參與的生物途徑及與特定疾病的關係，均已成為當前研究醣質生物學的重要領域。本論文即是針對醣苷水解酶來開發及合成活性標示探針。
在此研究中，我們以香豆素（Coumarin）的基本結構為核心，發展出本身不具螢光，卻能針對醣苷水解酶活性，經水解動作後發出螢光的活性探針。此類探針分子設計上的另一重點，是它們在與目標醣苷水解酶作用後會產生高活性的醌化甲基（quinone methide），可與鄰近帶有親核基的生物分子作用形成共價鍵進而達成固定化。本論文中我們針對不同醣苷水解酶的活性，包括beta-glucuronidase、beta-N-acetyl-glucosaminidase及beta-N-acetyl-galactosaminidase，合成出三種帶有不同醣基辨識單元（beta-GlcA、beta-GlcNAc及beta-GalNAc）的螢光團前驅物探針分子。

關鍵字

醣苷水解酶 ； 活性探針 ； 螢光探針 ； 醌化甲基 ； 香豆素

並列摘要

Abstract
Glycosidases, which catalyze the hydrolysis of glycosidic bonds in a variety of complex sugars, are extremely common enzymes in nature. Furthermore, they play crucial roles in carbohydrate metabolism and regulation of different cellular functions. Recent researches suggested that abnormalities in glycosidases have tight relationship with various diseases including cancer. Therefore, it is an urgent demand to develop inhibitors and probes for the glycosidases. In this thesis, we designed and synthesized molecular tools targeting glycosidases.　
Based on coumarin as a molecular framework, we have developed self-immobilizing fluorogenic activity-based probes. In addition, high reactive quinone methide produced after hydrolyzation can form covalent bond to neighboring nucleophilic sites. In this thesis, we synthesized the following three glycosidase-triggered turn-on fluorescent probes with different peracetylated sugars as recognition heads including beta-glucuronic acid (beta-GlcA), beta-N-acetyl-glucosamine (beta-GlcNAc) and beta-N-acetyl-galactosamine (beta-GalNAc), targeting different glycosidases: beta-glucuronidase, beta-N-acetyl-glucosaminidase and beta-N-acetyl-galactosaminidase respectively.

並列關鍵字

glycosidase ； activity-based probes ； fluorogenic probes ； quinone methide ； coumarin

參考文獻

(1) Haltiwanger, R. S.; Lowe, J. B. Role of glycosylation in development. Annu. Rev. Biochem. 2004, 73, 491-537.

(2) Parodi, A. J. Role of N-oligosaccharide endoplasmic reticulum processing reactions in glycoprotein folding and degradation. Biochem. J. 2000, 348 Pt 1, 1-13.

(3) Sacchettini, J. C.; Baum, L. G.; Brewer, C. F. Multivalent protein-carbohydrate interactions. A new paradigm for supermolecular assembly and signal transduction. Biochemistry 2001, 40, 3009-3015.

(4) Whittaker, G. R. Intracellular trafficking of influenza virus: clinical implications for molecular medicine. Expert. Rev. Mol. Med. 2001, 2001, 1-13.

(5) Ohtsubo, K.; Marth, J. D. Glycosylation in cellular mechanisms of health and disease. Cell 2006, 126, 855-867.