Basak S, Tomana M, Compans R W
Virus Res. 1985 Feb;2(1):61-8. doi: 10.1016/0168-1702(85)90060-7.
We have analyzed the pronase-derived glycopeptides of the hemagglutinin glycoproteins expressed from SV40 vectors carrying cloned cDNA copies of the HA gene and of HA isolated from influenza virions (A/Jap/305/57). The glycopeptides derived from he HA glycoprotein obtained from cloned genes were heterogeneous, ranging in size from 3800 to 2800 daltons. Upon treatment with neuraminidase, sialic acid was released from the glycopeptides and their size was reduced to 2900-2400 daltons. However, under the same conditions, no sialic acid was detected in the virion HA. The presence of sialic acid was confirmed by monosaccharide analysis of the HA glycoprotein derived from products of cloned genes. These results support the idea that during replication of influenza virus, the viral neuraminidase cleaves sialic acid from the HA glycoprotein in infected cells.
我们分析了从携带HA基因克隆cDNA拷贝的SV40载体表达的血凝素糖蛋白以及从流感病毒粒子（A/Jap/305/57）分离的HA中经链霉蛋白酶衍生的糖肽。从克隆基因获得的HA糖蛋白衍生的糖肽是异质的，大小范围为3800至2800道尔顿。用神经氨酸酶处理后，糖肽中的唾液酸被释放出来，其大小降至2900 - 2400道尔顿。然而，在相同条件下，病毒粒子HA中未检测到唾液酸。通过对克隆基因产物衍生的HA糖蛋白进行单糖分析，证实了唾液酸的存在。这些结果支持了这样一种观点，即在流感病毒复制过程中，病毒神经氨酸酶从感染细胞中的HA糖蛋白上切割下唾液酸。
