Short-chain oligopeptides with copper(II) binding properties: The impact of specific structural modifications on the copper(II) coordination abilities |
| |
Authors: | Agnieszka Matera-Witkiewicz Jolanta ?wi?tek-Koz?owska Alessandro Pratesi Luigi Messori |
| |
Institution: | a Department of Inorganic Chemistry, Medical University of Wroc?aw, Szewska 38, 50-139 Wroc?aw, Poland b Laboratory of Peptides & Proteins Chemistry & Biology c/o Department of Organic Chemistry, University of Florence, via della Lastruccia 13, 50019 Sesto Fiorentino, Firenze, Italy c Metals in Medicine Group (METMED), Department of Chemistry, University of Florence, via della Lastruccia 3, Sesto Fiorentino, Firenze, Italy |
| |
Abstract: | A series of linear tetrapeptides containing two histidyl residues in position 2 and 4, namely DHGH, DHGdH, KHGH, KHGdH, Ac-DHGH-NH2, Ac-DHGdH-NH2, Ac-KHGH-NH2, and Ac-KHGdH-NH2, were synthesized and characterised. Their copper(II) binding properties were investigated in depth through a variety of physicochemical methods. Potentiometric titrations were first carried out to establish the stoichiometry and the stability of the resulting copper(II)-peptide complexes. The copper(II) chromophores that are formed in the various cases in dependence of pH were subsequently characterised by extensive spectroscopic analysis (UV-Vis, EPR, CD) in strict correlation with potentiometric data. The effects of the nature of the first amino acid (Lys versus Asp) and of N-terminal amino group protection on copper(II) binding were specifically addressed. On turn, the careful comparison of the copper(II) coordination abilities of the linear peptides with those of their cyclic analogs provided insight into the effects of cyclization on the overall metal binding properties. |
| |
Keywords: | Metallopeptides Copper(II) complexes Histidine |
本文献已被 ScienceDirect 等数据库收录! |
|