Rapid binding of concanavalin A and maltose-polyrotaxane conjugates due to mobile motion of α-cyclodextrins threaded onto a poly(ethylene glycol)
Rapid binding of concanavalin A and maltose-polyrotaxane conjugates due to mobile motion of α-cyclodextrins threaded onto a poly(ethylene glycol)
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DOI：
10.1021/bc049809h
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发表时间：
2005-01-01
影响因子：
4.7
通讯作者：
Yui, N
中科院分区：
文献类型：
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作者：
Ooya, T;Utsunomiya, H;Yui, N
麦芽糖-聚轮烷缀合物（Mal-PRXs）是将麦芽糖缀合的α-环糊精（alpha-CD）连接到用苄氧羰基-L-酪氨酸封端的聚（乙二醇）（PEG）链上，其特征在于它们的分子运动和麦芽糖部分与来自剑形刀豆的伴刀豆球蛋白A（Con A）之间的多价相互作用的关系。Mal-PRX中α-CD C（1）、麦芽糖基C（1）和PEG亚甲基质子的自旋-晶格弛豫时间（T-1）和自旋-自旋弛豫时间（T-2）表明，聚轮烷中α-CD的移动的运动控制α-CD和PEG链中麦芽糖基的分子运动。具有22%、38%和53% α-CD穿线的Mal-PRX的缔合常数（K-a）分别为5.7 X 10（4）、1.1 X 10（6）和5.3 X 10（5）（M-1-麦芽糖）。最大的K。具有38% α-CD穿线的Mal-PRX的T-1和T-2值与麦芽糖基和α-CD的T-1和T-2值良好相关，表明Mal-PRX中麦芽糖缀合的α-CD的移动的运动有助于与Con A的最高亲和力。与Con A结合的初始速率也受麦芽糖缀合的α-CD的移动的运动控制。因此，我们得出结论，由于麦芽糖缀合的α-CD的移动的运动引起的高分子运动和Mal-PRX的多价性都有助于诱导快速Con A结合。
Maltose-polyrotaxane conjugates (Mal-PRXs), in which maltose-conjugated alpha-cyclodextrins (alpha-CDs) are threaded onto a poly(ethylene glycol) (PEG) chain capped with benzyloxycarbonyl-L-tyrosine, were characterized in terms of their molecular motion and the relation to multivalent interactions between the maltose moiety and concanavalin A from Canavalia ensiformis (Con A). Spin-lattice relaxation time (T-1) and spin-spin relaxation time (T-2) of alpha-CD C(1), maltosyl C(1), and PEG methylene protons in the Mal-PRXs revealed that the mobile motion of alpha-CDs in the polyrotaxane governed the molecular motion of maltosyl groups in alpha-CDs and threading PEG chain. The association constant (K-a) of the Mal-PRXs with 22, 38 and 53% of alpha-CD threading was 5.7 x 10(4), 1.1 x 10(6), and 5.3 x 10(5) (M-1-maltose), respectively. The largest K. value of the Mal-PRX with 38% of alpha-CD threading was well correlated with the T-1 and T-2 values of maltosyl groups and alpha-CD, suggesting that the mobile motion of maltose-conjugated alpha-CDs in the Mal-PRX contributes to the highest affinity with Con A. Initial rate of binding with Con A was also governed by the mobile motion of maltose-conjugated alpha-CDs. Therefore, we concluded that both highly molecular motion due to the mobile motion of maltose-conjugated alpha-CDs and multivalency of the Mal-PRXs contributes to inducing rapid Con A binding.