牡蛎体液糖蛋白的分离纯化及其理化性质分析

Isolation,Purification and Characterization of Glycoprotein from Oyster Juice

目的:从牡蛎体液中提取分离糖蛋白,对其理化性质进行初步研究。方法:运用凝胶柱层析(Sephadex G75)、离子交换层析法(Q Sepharose FF)和超滤法分离纯化得到糖蛋白S2,用SDS-PAGE凝胶电泳测其分子质量,高效液相色谱法测定氨基酸组成,红外光谱鉴定肽链结构,β-消去反应鉴定糖肽键类型,DSC表征其热变性。结果:SDS-PAGE凝胶电泳显示S2是纯度较高的组分,分子质量为21 ku;红外光谱呈现出典型糖类和肽键的特征吸收峰,肽链以α-螺旋构型存在;DSC显示热变性温度为113.5℃;β-消去反应表明糖肽键为N-糖苷键。

Objective： To study the preparation and the physicochemical characteristics of the glycoprotein from the Oyster Juice. Methods： The glycoprotein S2 was purified using Sephadex G75 gel chromatography, ion exchange（Q Sepharose FF） and ultrafiltration. The molecular weight, amino acid composition, structure of peptide chain, glycosidic linkage and thermal denature were measured using SDS-PAGE, HPLC, Fourier transform infrared （FTIR）, 13-eliminatiun reaction and DSC. Results and Conclusion： SDS-PAGE showed that the purity of $2 was high and the molecular weight was 21 ku. FTIR analysis showed the typical absorption of saccharide and the conformation of peptide chain was a-helix. The temperature of denature is 113.5 ℃. β-Elimination reaction demonstrated the existence of N-glycosidic linkage in S2.