GalNAc is transferred onto 3a

A sialyltransferase adds a terminal sialic acid moiety to protein 3a with an O-linked glycosyl side chain. This glycosylated form later is associated with the virion (Oostra et al, 2006).一种唾液酸转移酶将一个终端唾液酸基团添加至蛋白质3a的O-连接糖苷侧链。此糖基化形式随后与病毒粒子（Oostra等，2006年）相关联。