Xu G, Suzuki T, Maejima Y, Mizoguchi T, Tsuchiya M, Kiso M, Hasegawa A, Suzuki Y
Department of Biochemistry, University of Shizuoka, School of Pharmaceutical Science, Japan.
Glycoconj J. 1995 Apr;12(2):156-61. doi: 10.1007/BF00731360.
The sialidase of swine influenza A viruses of N1 and N2 subtypes, isolated from 1930 to 1992, was studied for substrate specificity with ganglio-series, lacto-series type II and GM3 gangliosides containing Neu5Ac alpha 2-3Gal, Neu5Gc alpha 2-3Gal and Neu5Ac alpha 2-6Gal linkages. All viral sialidases tested showed that the activity for hydrolysing substrates with Neu5Ac alpha 2-3Gal was higher than the activities with Neu5Gc alpha 2-3Gal and Neu5Ac alpha 2-6Gal linkages. When GM1b, GM3 and sialylparagloboside were used as substrates, the earliest strain (A/Wisconsin/15/30 H1N1, isolated in 1930) showed the activity ratio of Neu5Ac alpha 2-6Gal to Neu5Ac alpha 2-3Gal to be 0.13:0.2, and the ratio Neu5Gc alpha 2-3Gal/Neu5Ac alpha 2-3Gal to be 0.19:0.37, while those strains isolated from 1978 to 1992 exhibited ratios of 0.29:0.58 for Neu5Ac alpha 2-6Gal/Neu5Ac alpha 2-3Gal and 0.51:0.76 for Neu5Gc alpha 2-3Gal/Neu5Ac alpha 2-3Gal. The above results indicate that the substrate specificities of sialidases from swine influenza A viruses towards sialyl linkages and the molecular species of sialic acid are related to the year of isolation, i.e. strains isolated after 1978 exhibited higher activity towards Neu5Ac alpha 2-6Gal and Neu5Gc alpha 2-3Gal linkages when compared with strains isolated in an earlier year, 1930.
对1930年至1992年间分离出的N1和N2亚型甲型猪流感病毒的唾液酸酶进行了研究，以确定其对含有Neu5Acα2-3Gal、Neu5Gcα2-3Gal和Neu5Acα2-6Gal连接的神经节系列、乳糖系列II型和GM3神经节苷脂的底物特异性。所有测试的病毒唾液酸酶均显示，水解含有Neu5Acα2-3Gal底物的活性高于含有Neu5Gcα2-3Gal和Neu5Acα2-6Gal连接底物的活性。当使用GM1b、GM3和唾液酸副球蛋白作为底物时，最早的毒株（1930年分离的A/威斯康星/15/30 H1N1）显示Neu5Acα2-6Gal与Neu5Acα2-3Gal的活性比为0.13:0.2，Neu5Gcα2-3Gal/Neu5Acα2-3Gal的比值为0.19:0.37，而1978年至1992年间分离的毒株Neu5Acα2-6Gal/Neu5Acα2-3Gal的比值为0.29:0.58，Neu5Gcα2-3Gal/Neu5Acα2-3Gal的比值为0.51:0.76。上述结果表明，甲型猪流感病毒唾液酸酶对唾液酸连接和唾液酸分子种类的底物特异性与分离年份有关，即与1930年早期分离的毒株相比，1978年后分离的毒株对Neu5Acα2-6Gal和Neu5Gcα2-3Gal连接表现出更高的活性。
