Russo Krauss Irene, Pica Andrea, Merlino Antonello, Mazzarella Lelio, Sica Filomena
Department of Chemical Sciences, University of Naples `Federico II', Complesso Universitario di Monte Sant'Angelo, I-80126 Naples, Italy.
Acta Crystallogr D Biol Crystallogr. 2013 Dec;69(Pt 12):2403-11. doi: 10.1107/S0907444913022269. Epub 2013 Nov 19.
Potent second-generation thrombin aptamers adopt a duplex-quadruplex bimodular folding and recognize thrombin exosite II with very high affinity and specificity. A sound model of these oligonucleotides, either free or in complex with thrombin, is not yet available. Here, a structural study of one of these aptamers, HD22-27mer, is presented. The crystal structure of this aptamer in complex with thrombin displays a novel architecture in which the helical stem is enchained to a pseudo-G-quadruplex. The results also underline the role of the residues that join the duplex and quadruplex motifs and control their recruitment in thrombin binding.
强效第二代凝血酶适体采用双链-四链体双模块折叠结构，以非常高的亲和力和特异性识别凝血酶外位点II。目前尚无这些寡核苷酸游离态或与凝血酶复合物的完善模型。本文展示了其中一种适体HD22-27mer的结构研究。该适体与凝血酶复合物的晶体结构呈现出一种新颖的结构，其中螺旋茎与假G-四链体相连。研究结果还强调了连接双链和四链体基序并控制它们在凝血酶结合中募集的残基的作用。
