Self‐assembly of hairpin peptides mediated by Cu(II) ion: Effect of amino acid sequence

Abstract

The alteration of amino acid register in peptides could affect their folding properties and thus functions. The effect of sequence in metal ion induced folding of peptide/ protein is important in the design of new functional protein structures, such as biomimetics. In this paper, a set of hairpin peptides with identical composition but different histidine locations have been designed to exploit the metal ion-mediated peptide intramolecular folding transformation through the adjustment of histidine and lysine residue locations. The results demonstrated that the histidine positions in peptide sequence could dramatically affect the coordination modes between peptides and Cu(II) ion. The Cu(II) coordination could affect the secondary structure transformation and self-assembly along with electrostatic interaction and hydrogen bonding synergistically. Three molecules with VHVH sequence at each side of the turn segment (V D PPT) were apt to coordinate with Cu(II) ion with three or four histidines. The closer the VHVH motifs were to the turn segment, the more easier the molecules were to form β sheet structure with the promotion of Cu(II) ions. These results demonstrated that the purposeful location of key amino acids in peptides could achieve the controllable conformation transformation of hairpin peptides, which provides useful strategies for biomimetic design, such as metalloenzymes.

Divalent metal ion modulation of a simple peptide-based hydrogel: self-assembly and viscoelastic properties

“…This may be due to stable species formation at this ratio of Cu 2+ which is supported by the presence of a 2 : 1 C 14 -FH(Trt)-OH : Cu complex species found through mass spectrometry as stated earlier. Based on these spectroscopic results suggesting involvement of the amide backbone and literature, 54,57–60 potential structures have been hypothesized and shown in Fig. 8 demonstrating a metal ion binding pocket potentially formed by the imidazole and amide backbone in addition to free aromatic rings to allow for self-assembly through π-interactions into supramolecular nanostructures.…”

Coassembly Behavior and Rheological Properties of a β-Hairpin Peptide with Dicarboxylates

“…Because basic amino acid residues (histidines and lysines) in the molecule were protonated and positively charged at pH 4.0, CBHH could not fold intramolecularly due to the electrostatic repulsion. 22,27,28 In our previous studies, we showed that Cu(II) and Pt(IV) could induce the intramolecular folding and self-assembly of CBHH, and we also fabricated CuS and Pt nanomaterials under the regulation of CBHH. In the present study, we found that the addition of dicarboxylates promoted the β-sheet formation.…”

Peptide Design and Self-assembly into Targeted Nanostructure and Functional Materials

“…Another example of de novo designed β-hairpin peptide assembly was demonstrated by Xu and co-workers, in which Cu(II) coordination with the designed peptide having the βturn V D PPT sequence along with lysine and histidine residues showed concentration and pH dependent β-sheet nanofibrillar formation. 190 Nowick and co-workers, who have used a macrocyclic β-sheet forming peptide sequence consisting of two β-strands derived from Aβ 16−22 connected by two ornithine turn units to construct supramolecular double walled nanotubes. 189 They showed using extensive X-ray crystallography that the inner wall was composed of a network of hydrogen-bonded dimers and the outer wall comprised of a network of β barrel-like tetramers (Figure 12).…”