Analysis of 15 adenovirus hexon proteins reveals the location and structure of seven hypervariable regions containing serotype-specific residues
Analysis of 15 adenovirus hexon proteins reveals the location and structure of seven hypervariable regions containing serotype-specific residues
复制标题
DOI：
10.1128/jvi.70.3.1836-1844.1996
复制
发表时间：
1996-03-01
影响因子：
5.4
通讯作者：
Schnurr, DP
中科院分区：
文献类型：
--
作者：
CrawfordMiksza, L;Schnurr, DP
从候选人AV 48（85-0844）中首次测定了D亚属腺病毒（AV）的全长六邻体蛋白DNA和推导的氨基酸序列。将该序列与来自人A、B、C、D、F亚属、牛AV 3和小鼠AV 1的六邻体蛋白序列进行综合比较，发现在环1和2的250个可变残基中有7个离散的高变区（HVR），这些区域在血清型之间的长度不同，从2至38个残基，并且在人血清型中含有>99%的六邻体血清型特异性残基。与AV 2的公开晶体结构的比对建立了类型特异性区域的位置和结构。显示五个HVR是蛋白质暴露表面上的线性环的一部分，类似于小核糖核酸病毒衣壳蛋白中的病毒型特异性环或“蓬松物”。HVR由保守残基的共同框架支持，其中68%至75%是疏水性的。独特的序列限于七个HVR，使得这些区域中的一个或多个包含类型特异性中和表位。通过酶免疫测定，中和AV 48六邻体特异性抗血清识别对应于六个HVR的线性肽。亲和纯化去除所有肽反应性抗体没有显著降低中和滴度，凹槽肽反应性抗体没有中和，中和AV 48的人抗血清不识别线性肽，纯化的三聚体天然六邻体抑制中和，但单体热变性六邻体没有。我们得出结论，AV 48中和表位是复杂的和构象的。
The first full-length hexon protein DNA and deduced amino acid sequences of a subgenus D adenovirus (AV) were determined from candidate AV48 (85-0844), Comprehensive comparison of this sequence with hexon protein sequences from human subgenera A, B, C, D, F, bovine AV3, and mouse AV1 revealed seven discrete hypervariable regions (HVRs) among the 250 variable residues in loops 1 and 2, These regions differed in length between serotypes, from 2 to 38 residues, and contained >99% of hexon serotype specific residues among human serotypes, Alignment with the published crystal structure of AV2 established the location and structure of the type-specific regions, Five HVRs were shown to be part of linear loops on the exposed surfaces of the protein, analogous to the serotype-specific loops or ''puffs'' in picornavirus capsid proteins. The HVRs were supported by a common framework of conserved residues, of which 68 to 75% were hydrophobic. Unique sequences were limited to the seven HVRs, so that one or more of these regions contain the type-specific neutralization epitopes, A neutralizing AV48 hexon-specific antiserum recognized linear peptides that corresponded to six HVRs by enzyme immunoassay. Affinity-purification removal of all peptide-reactive antibodies did not significantly decrease the neutralization titer, fluted peptide-reactive antibodies did not neutralize, Human antisera that neutralized AV48 did not recognize linear peptides, Purified trimeric native hexon inhibited neutralization, but monomeric heat denatured hexon did nut, We conclude that the AV48 neutralization epitope(s) is complex and conformational.