Department of Inorganic Chemistry, Wroclaw Medical University, Borowska 211A, 50-552 Wrocław, Poland.
Int J Mol Sci. 2021 Jun 21;22(12):6628. doi: 10.3390/ijms22126628.
In this paper, we present findings from studying the interaction of copper(II) ions with the His-cyclopentapeptide and the role of proline used for the purpose of potentiometric titration and UV-Vis, CD and EPR spectroscopic measurements. Experiments of two homodetic peptides differing by one amino acid residue were conducted for a ligand to metal ratio of 1:1 in the pH range 2.5-11.0. The presented studies reveal that peptides form only mononuclear complexes, and the CuHL complex appears in the system first (for both L1 and L2). Study results show that the presence of Pro influences the structure of formed complexes and their stabilities and has a strong impact on the efficiency of copper(II) coordination.
本文通过研究铜（II）离子与 His-环五肽的相互作用，以及脯氨酸在电位滴定和紫外可见、圆二色和电子顺磁共振光谱测量中的作用，提出了一些研究结果。在 pH 值为 2.5-11.0 的范围内，对于配体与金属的比例为 1:1，进行了两种同源肽相差一个氨基酸残基的实验。研究结果表明，这些肽只形成单核配合物，并且在该体系中首先出现 CuHL 配合物（对于 L1 和 L2 都是如此）。研究结果表明，脯氨酸的存在会影响形成的配合物的结构及其稳定性，并且对铜（II）的配位效率有很大的影响。
