Urry D W, Ohnishi M, Walter R
Proc Natl Acad Sci U S A. 1970 May;66(1):111-6. doi: 10.1073/pnas.66.1.111.
The secondary structure of the cyclic moiety of oxytocin and deamino-oxytocin has been determined by nuclear magnetic resonance spectroscopy (220 MHz). Oxytocin, in a dimethylsulfoxide-methanol mixture, contains a beta-turn involving the sequence -L-tyrosyl-L-isoleucyl-L-glutaminyl-L-asparaginyl-. Deamino-oxytocin, in addition to the beta-turn, contains a hydrogen bond involving the amide hydrogen of the tyrosine residue and the peptide carbonyl group of the asparagine residue, resulting in an antiparallel beta-type conformation for the ring component. An initial attempt has been made to relate conformational features of the hormonal peptides to their biological activity.
已通过核磁共振光谱法(220兆赫)确定了催产素和脱氨基催产素环状部分的二级结构。在二甲基亚砜 - 甲醇混合物中的催产素含有一个涉及-L-酪氨酰-L-异亮氨酰-L-谷氨酰胺基-L-天冬酰胺基序列的β-转角。脱氨基催产素除了含有β-转角外,还含有一个涉及酪氨酸残基的酰胺氢和天冬酰胺残基的肽羰基的氢键,导致环组分具有反平行β型构象。已初步尝试将这些激素肽的构象特征与其生物活性联系起来。