5种凡纳滨对虾血蓝蛋白的糖基化修饰及功能对比分析  

Comparative Analyses of Five Hemocyanin Isomers from Shrimp Litopenaeus vannamei

作　　者：章跃陵[1,2] 邢立刚[1,3] 严芳[1,2] 黄锡望[1] 杜志恒[1] 乔杰[1] 林仲旸[1] 李远友[1,2] 

机构地区：[1]汕头大学理学院生物学系,广东汕头515063 [2]汕头大学海洋生物研究所,广东汕头515063 [3]长江师范学院生物实验教学中心,重庆408100

出　　处：《中国生物化学与分子生物学报》2009年第7期655-661,共7页Chinese Journal of Biochemistry and Molecular Biology

基　　金：国家自然科学基金项目(No.30871939);广东省科技计划项目(No.2007B020701006;2006A36502004;2006A36502001;2007A032600003);广东省自然科学基金项目(No.06027212)~~

摘　　要：血蓝蛋白是近年来发现的一种多功能蛋白,但其功能多样性的分子基础尚不清楚.本研究采用亲和层析、糖含量测定、凝集素印迹等技术在凡纳滨对虾血清中发现5种糖含量各不相同的血蓝蛋白:HMC、HMCb-、HMCb、HMCs-和HMCs,其中HMCs-糖含量最高,HMCb最低,前者约为后者的5倍.继而运用非特异性免疫学实验技术对其功能进行对比分析.结果显示,不同糖基化血蓝蛋白的免疫学活性不同,HMCs-具有较强的红细胞凝集活性和酚氧化酶活性,HMCb-和HMC分别具有较强的细菌凝集活性和溶血活性.特别是当血蓝蛋白糖基被氧化后,5种血蓝蛋白的凝集活性、溶血活性全部丧失,酚氧化酶活性下降约11～28倍.由此推测,血蓝蛋白糖基修饰多样性可能是其功能多样性的分子基础之一.Hemocyanin is a muhifunctional protein and recently recognized with immune activities. In the present study, five hemocyanin isomers glycolysed to different degrees in the haemolymph of Litopenaeus vannamei, HMC, HMCb, HMCb, HMCs- and HMCs, were purified and characterized by affinity chromatography, total glycan measurement and lectin-blotting. HMCs- have the highest level of total glycan content, about 5 folds as compared to HMCb with the lowest composition of glycans. The functional diversities of the five hemocyanin isomers were demonstrated by non-specific immune assays with different activities. HMCs- showed strongest hemagglutinative and phenoloxidase activities, HMCb- and HMC demonstrated the strongest agglutinative and hemolytic effects. The agglutinative （hemagglutinative） and hemolytic activities in all five hemocyanin isomers were completely abolished when their carbohydrate chains were oxidated, and the phenoloxidase activities were reduced by 11 - 28 folds. These findings suggested that the glycosylation diversity contributed to the functional diversity of hemocyanin.

关 键 词：血蓝蛋白 多功能 糖基化 多样性 分子基础 

分 类 号：Q71[生物学—分子生物学]