Date of Award

2012

Degree Type

Thesis

Department

Chemistry

First Advisor

Sun, Xue-Long

Subject Headings

Boron, Acids, Glycomics, Ligands (Biochemistry), Surface plasmon resonance, Boronic acid, Glycan, Glycomics, Lectin, Protein Conjugate, Surface Plasmon Resonance(SPR)

Abstract

Cell surface carbohydrates existing as glycoproteins and glycolipids represent the first information about the cell with the outside world and are closely involved in various biological processes such as cell communication, and the molecular recognition and cell targeting. However, the mechanisms of most of the processes at the molecular level are still unclear. It is therefore very important to develop specific carbohydrate-binding molecules for a fast, efficient, sensitive and accurate analysis of complex carbohydrates structures and functions, known as glycomics. In addition, certain carbohydrate-binding molecules can be used in medical applications such as biomarkers for diseases diagnosis and targeted drug delivery applications. In this thesis study, I conducted synthesis, characterization and glyco-capturing capacity investigation of bovine serum albumin (BSA)-boronic acid (BA) conjugates as lectin mimetics. The BSA-BA conjugates were synthesized by amidation of carboxylic acid groups in BSA with aminophenyl boronic acid in the presence of EDC, and were characterized by Alizarin Red S (ARS) assay and SDS-PAGE gel. The BSA-BA conjugates were immobilized onto maleimide-functionalized silica beads and their sugar capturing capacity and specificity were confirmed by Alizarin Red displacement assay. As a result, the interactions between the sugars and SB-BSA-BA was in the order of Fructose >Galactose >Mannose >Fucose >Lactose >Sialic Acid >GlcNAc >Glucose at pH 7.4 and Fructose >Fucose >Lactose >Galactose >Mannose >GlcNAc >Sialic Acid >Glucose at pH 8.3. Further, SPR analysis of BSA-BA-based glyco-capturing test was conducted by immobilizing BSA-BA onto SPR gold chip. As a result, the interactions between the sugars and BSA-BA on the gold chip were in the order of Lactose >Mannose >Glucose >Fucose >Sialic acid >Fructose >GlcNAc >Galactose at pH7.4 and Glucose >Galactose >Mannose >GlcNAc >Fructose >Fucose >Sialic acid >Lactose at pH8.3. Overall, I have developed a BSA-BA-based lectin mimetics for glycocapturing

Download

Included in

Chemistry Commons

COinS