TY - JOUR

T1 - Folding Topology of a Short Coiled-Coil Peptide Structure Templated by an Oligonucleotide Triplex

AU - Lou, Chenguang

AU - Christensen, Niels Johan

AU - Martos Maldonado, Manuel Cristo

AU - Midtgaard, Søren Roi

AU - Ejlersen, Maria

AU - Thulstrup, Peter Waaben

AU - Sørensen, Kasper Kildegaard

AU - Jensen, Knud Jørgen

AU - Wengel, Jesper

PY - 2017

Y1 - 2017

N2 - The rational design of a well-defined protein-like tertiary structure formed by small peptide building blocks is still a formidable challenge. By using peptide-oligonucleotide conjugates (POC) as building blocks, we present the self-assembly of miniature coiled-coil α-helical peptides guided by oligonucleotide duplex and triplex formation. POC synthesis was achieved by copper-free alkyne-azide cycloaddition between three oligonucleotides and a 23-mer peptide, which by itself exhibited multiple oligomeric states in solution. The oligonucleotide domain was designed to furnish a stable parallel triplex under physiological pH, and to be capable of templating the three peptide sequences to constitute a small coiled-coil motif displaying remarkable α-helicity. The formed trimeric complex was characterized by ultraviolet thermal denaturation, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering (SAXS), and molecular modeling. Stabilizing cooperativity was observed between the trimeric peptide and the oligonucleotide triplex domains, and the overall molecular size (ca. 12nm) in solution was revealed to be independent of concentration. The topological folding of the peptide moiety differed strongly from those of the individual POC strands and the unconjugated peptide, exclusively adopting the designed triple helical structure.

AB - The rational design of a well-defined protein-like tertiary structure formed by small peptide building blocks is still a formidable challenge. By using peptide-oligonucleotide conjugates (POC) as building blocks, we present the self-assembly of miniature coiled-coil α-helical peptides guided by oligonucleotide duplex and triplex formation. POC synthesis was achieved by copper-free alkyne-azide cycloaddition between three oligonucleotides and a 23-mer peptide, which by itself exhibited multiple oligomeric states in solution. The oligonucleotide domain was designed to furnish a stable parallel triplex under physiological pH, and to be capable of templating the three peptide sequences to constitute a small coiled-coil motif displaying remarkable α-helicity. The formed trimeric complex was characterized by ultraviolet thermal denaturation, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering (SAXS), and molecular modeling. Stabilizing cooperativity was observed between the trimeric peptide and the oligonucleotide triplex domains, and the overall molecular size (ca. 12nm) in solution was revealed to be independent of concentration. The topological folding of the peptide moiety differed strongly from those of the individual POC strands and the unconjugated peptide, exclusively adopting the designed triple helical structure.

KW - Circular dichroism

KW - Click chemistry

KW - Molecular modeling

KW - Oligonucleotides

KW - Peptides

U2 - 10.1002/chem.201700971

DO - 10.1002/chem.201700971

M3 - Journal article

C2 - 28383784

AN - SCOPUS:85019120398

VL - 23

SP - 9297

EP - 9305

JO - Chemistry: A European Journal

JF - Chemistry: A European Journal

SN - 0947-6539

IS - 39

ER -