Hölzemann G, Pachler K G
Medicinal Chemistry Department, E. Merck, Darmstadt, Federal Republic of Germany.
Int J Pept Protein Res. 1989 Aug;34(2):139-47. doi: 10.1111/j.1399-3011.1989.tb01503.x.
The undecapeptide physalaemin was investigated by n.m.r. spectroscopy in DMSO solution under acidic and neutral conditions. Large changes of the NH chemical shifts and the temperature gradients of the NH protons occurred on going from pH 3.5 to pH 7.0 for residues around the charged amino acids Asp and Lys. At pH 3.5 the data are in accord with a flexible conformation of the peptide. The results at neutral pH are interpreted in terms of a folded structure having two interresidue and one intraresidue hydrogen bond. They include a beta turn with proline in position i + 1 and asparagine in position i + 2.
在酸性和中性条件下，通过核磁共振光谱法在二甲亚砜溶液中对十一肽 Physalaemin 进行了研究。对于带电荷的氨基酸天冬氨酸（Asp）和赖氨酸（Lys）周围的残基，从pH 3.5变为pH 7.0时，NH化学位移和NH质子的温度梯度发生了很大变化。在pH 3.5时，数据与该肽的柔性构象一致。中性pH下的结果解释为具有两个残基间和一个残基内氢键的折叠结构。它们包括一个β转角，其中脯氨酸位于i + 1位，天冬酰胺位于i + 2位。
