Ooya Tooru, Eguchi Masaru, Yui Nobuhiko
School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Tatsunokuchi, Ishikawa 923-1292, Japan.
J Am Chem Soc. 2003 Oct 29;125(43):13016-7. doi: 10.1021/ja034583z.
High molecular mobility of maltose-conjugated alpha-cyclodextrins (alpha-CDs) along a poly(ethylene glycol) (PEG) chain due to the mechanically locked structure of polyrotaxanes enhanced multivalent interactions between maltose and concanavalin A (Con A). When maltose groups are conjugated with alpha-CDs that were threaded onto a PEG capped with benzyloxycarbonyl l-tyrosine (polyrotaxane), Con A-induced hemagglutination was greatly inhibited by polyrotaxanes with a certain threading % of alpha-CDs. Such an inhibitory effect was significantly superior to the other type of conjugates, in which poly(acrylic acid) was used as a backbone for maltose conjugation. The spin-spin relaxation time (T2) of the maltose C(1) proton in the polyrotaxane at a typical alpha-CD threading % was significantly larger than that of any other conjugate, which was well related to the inhibitory effect. Therefore, we concluded that the high mobility of maltose groups along the polyrotaxane structure contributes to enhanced Con A recognition.
由于聚轮烷的机械锁定结构，麦芽糖共轭α-环糊精（α-CDs）沿聚乙二醇（PEG）链具有高分子迁移率，增强了麦芽糖与伴刀豆球蛋白A（Con A）之间的多价相互作用。当麦芽糖基团与穿在苄氧羰基-L-酪氨酸封端的PEG上的α-CDs共轭时（聚轮烷），具有一定α-CDs穿入率的聚轮烷极大地抑制了Con A诱导的血细胞凝集。这种抑制作用明显优于其他类型的共轭物，其中聚丙烯酸用作麦芽糖共轭的主链。在典型的α-CD穿入率下，聚轮烷中麦芽糖C(1)质子的自旋-自旋弛豫时间（T2）明显大于任何其他共轭物，这与抑制作用密切相关。因此，我们得出结论，麦芽糖基团沿聚轮烷结构的高迁移率有助于增强Con A识别。
