Matsuura Kazunori, Hibino Miki, Ikeda Takayasu, Yamada Yoshinao, Kobayashi Kazukiyo
Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan.
Chemistry. 2004 Jan 23;10(2):352-9. doi: 10.1002/chem.200305465.
We describe herein the relationship between the spatial arrangement of self-organized galactose clusters and lectin recognition. beta-Galactose-modified deoxyuridine phosphoramidite was synthesized and applied to solid-phase synthesis to provide 18-, 20-, and 22-mers of site-specifically galactosylated oligodeoxynucleotides (Gal-ODNs). These Gal-ODNs were self-organized through hybridization with the corresponding 18-, 20-, and 22-mers of half-sliding complementary ODNs (hsc-ODNs) to give periodic galactoside clusters. The self-organization of ODNs was confirmed by size exclusion chromatography and gel electrophoresis. The binding of the Gal-clusters to the FITC-labeled RCA(120) lectin was analyzed by monitoring the change in fluorescence intensity. The assembly of 20-mer Gal-ODN with the 20-mer hsc-ODN was strongly and cooperatively recognized by the lectin. The 18-mer assembly was bound more weakly and less cooperatively, and the 22-mer assembly was minimally bound to the lectin. RCA(120) lectin recognized not only the density of galactoside residues, but also the spatial arrangement. The size of the Gal cluster was estimated from the association constant of Gal-ODN with hsc-ODN. The relationship between lectin-recognition and Gal-cluster size is also discussed.
我们在此描述了自组装半乳糖簇的空间排列与凝集素识别之间的关系。合成了β-半乳糖修饰的脱氧尿苷亚磷酰胺，并将其应用于固相合成，以提供位点特异性半乳糖基化寡脱氧核苷酸（Gal-ODN）的18聚体、20聚体和22聚体。这些Gal-ODN通过与相应的18聚体、20聚体和22聚体的半滑动互补ODN（hsc-ODN）杂交进行自组装，形成周期性半乳糖苷簇。通过尺寸排阻色谱和凝胶电泳确认了ODN的自组装。通过监测荧光强度的变化分析了Gal簇与异硫氰酸荧光素标记的RCA(120)凝集素的结合。20聚体Gal-ODN与20聚体hsc-ODN的组装体被凝集素强烈且协同地识别。18聚体组装体的结合较弱且协同性较差，22聚体组装体与凝集素的结合最少。RCA(120)凝集素不仅识别半乳糖苷残基的密度，还识别其空间排列。根据Gal-ODN与hsc-ODN的缔合常数估算了Gal簇的大小。还讨论了凝集素识别与Gal簇大小之间的关系。
