Feyzi E, Trybala E, Bergström T, Lindahl U, Spillmann D
Department of Medical and Physiological Chemistry, Uppsala University, Biomedical Center, S-751 23 Uppsala, Sweden.
J Biol Chem. 1997 Oct 3;272(40):24850-7. doi: 10.1074/jbc.272.40.24850.
Cell surface heparan sulfates mediate primary attachment of herpes simplex virus type 1, the first step in virus invasion of the cells. Removal of the host cell heparan sulfate results in a significantly diminished susceptibility of the cell to virus infection. On the virus envelope, glycoprotein C has been identified as the major binding site for heparan sulfate in the primary attachment of the virus to host cells. Using selectively desulfated heparins and metabolically labeled host cell heparan sulfate, we have analyzed the structural requirements of heparan sulfate to provide binding sites for glycoprotein C and the whole virus. Employing glycoprotein C affinity chromatography and a virus binding assay, we subfractionated oligosaccharides derived from heparan sulfate and partially desulfated heparin into selectively bound and unbound pools. These were chemically depolymerized and analyzed at the disaccharide level. The shortest glycoprotein C-binding fragment consisted of 10-12 monosaccharide units containing at least one 2-O- and one 6-O-sulfate group that have to be localized in a sequence-specific way, based on the finding that bound and unbound HS fragments do not differ in charge or composition. The binding sequence is found within N-sulfated blocks of heparan sulfate, although several N-acetyl groups can be tolerated within the minimal binding sequence. These minimal requirements for herpes simplex virus type 1 binding to heparan sulfate are clearly distinct from other identified protein binding sites.
细胞表面硫酸乙酰肝素介导单纯疱疹病毒1型的初始附着，这是病毒侵入细胞的第一步。去除宿主细胞硫酸乙酰肝素会导致细胞对病毒感染的易感性显著降低。在病毒包膜上，糖蛋白C已被确定为病毒与宿主细胞初始附着过程中硫酸乙酰肝素的主要结合位点。我们使用选择性脱硫肝素和代谢标记的宿主细胞硫酸乙酰肝素，分析了硫酸乙酰肝素为糖蛋白C和整个病毒提供结合位点的结构要求。利用糖蛋白C亲和色谱法和病毒结合试验，我们将源自硫酸乙酰肝素和部分脱硫肝素的寡糖亚分级为选择性结合和未结合的组分。这些组分经过化学解聚，并在二糖水平上进行分析。最短的糖蛋白C结合片段由10 - 12个单糖单元组成，包含至少一个2 - O - 和一个6 - O - 硫酸基团，基于结合和未结合的硫酸乙酰肝素片段在电荷或组成上没有差异这一发现，这些基团必须以序列特异性方式定位。结合序列存在于硫酸乙酰肝素的N - 硫酸化区域内，尽管在最小结合序列中可以耐受几个N - 乙酰基团。单纯疱疹病毒1型与硫酸乙酰肝素结合的这些最低要求明显不同于其他已确定的蛋白质结合位点。
