An examination of the binding behavior of histidine-containing peptides with immobilized metal complexes derived from the macrocyclic ligand, 1,4,7-triazacyclononane |
| |
Authors: | Bim Graham Peter Comba Milton T W Hearn Leone Spiccia |
| |
Institution: | (1) ARC Special Research Center for Green Chemistry, Monash University, Claylon, VIC, 3800, Australia;(2) School of Chemistry, Monash University, Claylon, VIC , 3800, Australia;(3) Anorganisch-Chemisches Institut, University of Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany |
| |
Abstract: | In this study, two different experimental approaches have been employed to examine the binding behavior of histidine-containing
peptides with metal ion complexes derived from the macrocyclic ligand 1,4,7-triazacyclononane (tacn). Firstly, a molecular
modeling approach has been employed to derive the strain energies for test peptide sequences that have a predicted propensity
to readily adopt an α-helical conformation. To this end, binuclear metal complexes were examined with peptides containing
two histidine residues in different locations in a pair of peptides of the same composition but different sequence. These
modeling results indicate that there are no energetic constraints for two-point binding to occur with dicopper(II) binuclear
complexes when two histidine residues are appropriately placed in an α-helical conformation. Secondly, binding experiments
were carried out to establish the effect of one or more histidine residues within a peptide sequence on the affinity of a
peptide for these Cu(II)–tacn derived binuclear complexes when immobilized onto a chromatographic support material. The results
confirm that for all chelating systems, higher affinity is achieved as the histidine number in the peptide structure increases,
although the relative location of the histidine residues in these small peptides did not introduce a significant constraint
to the conformation on interacting with the immobilized Cu(II) binuclear complexes. |
| |
Keywords: | Macrocyclic ligands Metal ion binding Peptide interaction Molecular modeling Cu(II) binuclear complexes |
本文献已被 SpringerLink 等数据库收录! |
|