Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany.
Chem Commun (Camb). 2020 Apr 28;56(33):4539-4542. doi: 10.1039/d0cc01285h. Epub 2020 Mar 23.
Mixed 2'-F-riboguanosine and 2'-F-arabinoguanosine disubstitutions of a hybrid-type G-quadruplex are found to induce a refolding into two alternative structures with different types of V-loops upon positional exchange of the two G analogs. While conformational preferences of the incorporated G surrogates fail to fully account for the observed rearrangements, additional hydrogen bonds with a fluorine acceptor are suggested to be critical determinants of the two distinct V-loop conformers imposing different tetrad polarities.
混合的 2'-F-核糖鸟嘌呤核苷和 2'-F-阿拉伯糖鸟嘌呤核苷二取代物的杂交型 G-四链体被发现诱导在两个 G 类似物的位置交换时发生重折叠为两种具有不同类型 V 环的替代结构。虽然掺入的 G 取代物的构象偏好不能完全解释观察到的重排，但与氟受体的额外氢键被认为是两个不同 V 环构象体的关键决定因素，它们施加不同的四联体极性。
