Tu A T, Bjarnason J B, Hruby V J
Biochim Biophys Acta. 1978 Apr 26;533(2):530-3. doi: 10.1016/0005-2795(78)90399-9.
The peptide backbone conformation and salient structural details of oxytocin were examined by laser Raman spectroscopy. Spectra were obtained in the solid phase, water, 2H2O, and dimethyl sulfoxide solutions. A distinct Amide I band was obtained at 1663 cm-1 for aqueous and deuterated samples and 1666 cm-1 for the solid sample. A relatively high frequency Amide III band at 1260 cm-1 was obtained. It is concluded that these Amide I and III bands arise from the "beta-turn"-like conformation of oxytocin. The tyrosine side chain, according to the I850 cm-1/I830 cm-1 intensity ratio, is exposed to the solvent. The S-S stretching vibration at 512 cm-1 indicates the conformation of C-C-S-S-C-C in the disulfide bridge of oxytocin in the ring is gauche-gauche-gauche.
通过激光拉曼光谱研究了催产素的肽主链构象和显著的结构细节。在固相、水、重水和二甲基亚砜溶液中获得了光谱。水性和氘代样品在1663 cm-1处获得了明显的酰胺I带，固体样品在1666 cm-1处获得了该带。在1260 cm-1处获得了相对高频的酰胺III带。得出的结论是，这些酰胺I和III带源于催产素的“β-转角”样构象。根据I850 cm-1/I830 cm-1强度比，酪氨酸侧链暴露于溶剂中。512 cm-1处的S-S伸缩振动表明环中催产素二硫键的C-C-S-S-C-C构象为左-左-左。
