环八肽cyclo（Ala-Leu-Pro-Gly）2的构象和离子结合特性

Conformational and ion binding properties of a cyclic octapeptide, cyclo (Ala-Leu-Pro-Gly)2.

作者信息

Jois D S, Easwaran K R, Bednarek M, Blout E R

机构信息

Molecular Biophysics Unit, Indian Institute of Science, Bangalore.

出版信息

Biopolymers. 1992 Aug;32(8):993-1001. doi: 10.1002/bip.360320810.

DOI:10.1002/bip.360320810

PMID:1420982

Abstract

The conformation and ion-binding characteristics of a cyclic octapeptide, cyclo (Ala-Leu-Pro-Gly)2, in a liphophilic solvent, acetonitrile, have been studied using CD and nmr spectroscopy. The peptide binds preferentially to divalent cations such as calcium, magnesium, and barium. The conformations of the free cyclic peptide and its calcium complex are very similar with well-defined beta- and gamma-turns. The cyclic peptide readily forms equimolar and possibly 2:1 (peptide:cation) complexes with divalent cations.

摘要

利用圆二色光谱（CD）和核磁共振光谱（nmr）研究了环八肽环（丙氨酸-亮氨酸-脯氨酸-甘氨酸）₂在亲脂性溶剂乙腈中的构象和离子结合特性。该肽优先结合二价阳离子，如钙、镁和钡。游离环肽及其钙络合物的构象非常相似，具有明确的β-转角和γ-转角。环肽能与二价阳离子轻易形成等摩尔以及可能的2:1（肽:阳离子）络合物。