Chemistry Department, Moscow State University, 119991 Moscow, Russia.
Biogenec Joint-Stock Company, Moscow Region, 142290 Pushchino, Russia.
Int J Mol Sci. 2022 Jan 5;23(1):557. doi: 10.3390/ijms23010557.
Nucleic acid aptamers specific to S-protein and its receptor binding domain (RBD) of SARS-CoV-2 (severe acute respiratory syndrome-related coronavirus 2) virions are of high interest as potential inhibitors of viral infection and recognizing elements in biosensors. Development of specific therapy and biosensors is complicated by an emergence of new viral strains bearing amino acid substitutions and probable differences in glycosylation sites. Here, we studied affinity of a set of aptamers to two Wuhan-type RBD of S-protein expressed in Chinese hamster ovary cell line and that differ in glycosylation patterns. The expression system for the RBD protein has significant effects, both on values of dissociation constants and relative efficacy of the aptamer binding. We propose glycosylation of the RBD as the main force for observed differences. Moreover, affinity of a several aptamers was affected by a site of biotinylation. Thus, the robustness of modified aptamers toward new virus variants should be carefully tested.
针对严重急性呼吸综合征相关冠状病毒 2 （SARS-CoV-2）病毒粒子的 S 蛋白及其受体结合域（RBD）的核酸适体是作为病毒感染潜在抑制剂和生物传感器识别元件的研究热点。由于新的病毒株带有氨基酸取代和糖基化位点可能存在差异，因此特异性治疗和生物传感器的开发变得复杂。在这里，我们研究了一组适体与在中华仓鼠卵巢细胞系中表达的两种武汉型 S 蛋白 RBD 的亲和力，它们在糖基化模式上存在差异。RBD 蛋白的表达系统对解离常数的值和适体结合的相对效力都有显著影响。我们提出 RBD 的糖基化是观察到差异的主要原因。此外，几个适体的亲和力受到生物素化位点的影响。因此，应该仔细测试修饰适体对新型病毒变体的稳健性。
