聚（α-氨基酸）的金属配合物。聚（L-赖氨酸）、聚（L-鸟氨酸）和聚（L-二氨基丁酸）的铜（II）配合物的电位滴定和圆二色性研究。

Metal complexes of poly(alpha-amino acids). A potentiometric and circular dichroism investigation of Cu(II) complexes of poly(L-lysine), poly(L-ornithine), and poly(L-diaminobutyric acid).

作者信息

Palumbo M, Cosani A, Terbojevich M, Peggion E

出版信息

Macromolecules. 1977 Jul-Aug;10(4):813-20. doi: 10.1021/ma60058a018.

PMID:19653

Abstract

The conformational properties of cupric complexes of poly(L-lysine), poly(L-ornithine), and poly(L-diaminobutyric acid) have been investigated by potentiometric, visible and UV absorption, and circular dichroism (CD) techniques. The three polymers form two kinds of complexes stable at pH less than 8.5 (type I complexes) and at pH less than 8.5 (type II complexes). It has been found that in the low pH complexes of poly(L-diaminobutyric acid) at least one deprotonated amido nitrogen is coordinated to cupric ions. Type II complexes involve always amide nitrogens in the coordination sphere of Cu(II). Evidence is presented that the structure of such complexes is not compatible with the alpha-helical conformation of the peptide backbone.

摘要

通过电位滴定、可见和紫外吸收以及圆二色性（CD）技术研究了聚（L-赖氨酸）、聚（L-鸟氨酸）和聚（L-二氨基丁酸）的铜配合物的构象性质。这三种聚合物形成了两种在pH小于8.5时稳定的配合物（I型配合物）和在pH小于8.5时稳定的配合物（II型配合物）。已经发现，在聚（L-二氨基丁酸）的低pH配合物中，至少一个去质子化的酰胺氮与铜离子配位。II型配合物总是涉及Cu（II）配位球中的酰胺氮。有证据表明，这种配合物的结构与肽主链的α-螺旋构象不兼容。