Walter R, Glickson J D
Proc Natl Acad Sci U S A. 1973 Apr;70(4):1199-203. doi: 10.1073/pnas.70.4.1199.
The usefulness of 2,2,2-trifluoroethanol titration as a means of distinguishing between intramolecular peptide-peptide hydrogen bonding on the one hand and intermolecular peptide-peptide and peptide-solvent hydrogen bonding on the other has been investigated with neurohypophyseal hormones, and the results have been compared with those of other methods. The chemical shifts (220 MHz) of the resonances of amide NH and aromatic CH protons of oxytocin, lysine vasopressin, deamino-lysine vasopressin, and deamino-8-tosyllysine vasopressin were monitored as the solvent composition was progressively varied from 100% dimethylsulfoxide to 100% 2,2,2-trifluoroethanol. The overall backbone conformation of oxytocin appears to be retained, and possibly somewhat stabilized, during the solvent transition, while the backbone, particularly the acyclic component, of lysine vasopressin and its analogs is subject to solvent-induced perturbation.
已利用神经垂体激素研究了2,2,2-三氟乙醇滴定法在区分分子内肽-肽氢键与分子间肽-肽及肽-溶剂氢键方面的实用性,并将结果与其他方法的结果进行了比较。随着溶剂组成从100%二甲基亚砜逐渐变化至100% 2,2,2-三氟乙醇,监测了催产素、赖氨酸加压素、脱氨基赖氨酸加压素和脱氨基-8-甲苯磺酰赖氨酸加压素的酰胺NH和芳香族CH质子共振的化学位移(220 MHz)。在溶剂转变过程中,催产素的整体主链构象似乎得以保留,甚至可能有所稳定,而赖氨酸加压素及其类似物的主链,尤其是无环部分,会受到溶剂诱导的扰动。