Influence of the position of two dehydro-amino acids residues in the oligopeptide sequence on the binding ability towards Cu(II) ions
Abstract Studies on the binding ability of bis-dehydro-hexa- and pentapeptides have shown that the hexapeptides bind Cu+2 with similar efficacy as pentapeptides. The increase of distance between two dehydro-amino acid residues in the peptide backbone has no impact on the efficacy in metal ion binding. The type of isomeration [(Z) or (E)] has an influence on the coordination of the metal ion only to the first amide nitrogen.
Impact of α,β-dehydroamino acid residues on the binding abilities of di-, tri- and tetra-peptides
Insertion of a dehydroamino acid residue into a sequence of di-, tri- or tetra-peptide changed considerably the binding abilities of peptide ligands towards copper(II) ions. Potentiometric and spectroscopic (EPR, UV-VIS and CD) data have shown that the amide nitrogen of the dehydroamino acid residue is more effective in co-ordination than its parent analogue. In the case of the bulky ΔPhe residue also the (Z–E) isomerisation has a critical impact on the co-ordination equilibria in the system studied.
Binding abilities of dehydropeptides towards Cu(II) and Ni(II) ions. Impact of Z–E isomerization on metal ion binding
The study on the binding ability of dehydro-tri- and tetrapeptides has shown that the alpha,beta-double bond has a critical effect on the peptide coordination to metal ions. It may affect the binding of the vicinal amide nitrogens by the electronic effect and stabilize the complex due to steric effects. The (Z) isomer is the most effective in stabilizing of the complexes formed. The presence of large side chain in the dehydroamino acid residue may also be critical for the coordination mode in the metallopeptide systems.
Dipeptides of S-Substituted Dehydrocysteine as Artzyme Building Blocks: Synthesis, Complexing Abilities and Antiproliferative Properties †
Background: Dehydropeptides are analogs of peptides containing at least one conjugate double bond between α,β-carbon atoms. Its presence provides unique structural properties and reaction centre for chemical modification. In this study, the series of new class of dipeptides containing S-substituted dehydrocysteine with variety of heterocyclic moieties was prepared. The compounds were designed as the building blocks for the construction of artificial metalloenzymes (artzymes). Therefore, the complexing properties of representative compounds were also evaluated. Furthermore, the acknowledged biological activity of natural dehydropeptides was the reason to extend the study for antiproliferativ…
Coordination ability of pentapeptides with two dehydro-amino acid residues inserted into their sequences.
The study on the binding ability of tested ligands have shown that insertion of two dehydro-amino acid residues into peptide sequences makes them more effective in metal ion binding than ligands with one dehydro-amino acid residue. The ligand with two Z(Delta)Phe residue form more stable complexes than his analogues with one Z(Delta)Phe residue. Interesting is this that position of Z(Delta)Phe residue in peptide chain have impact on Cu(II)-complexes formation.