X-ray Crystallographic Structure and Solution Behavior of an Antiparallel Coiled-Coil Hexamer Formed by de Novo Peptides.Spencer, R.K., Hochbaum, A.I.
(2016) Biochemistry 55: 3214-3223
- PubMed: 27192036
- DOI: 10.1021/acs.biochem.6b00201
- Primary Citation of Related Structures:
- PubMed Abstract:
The self-assembly of peptides and proteins into higher-ordered structures is encoded in the amino acid sequence of each peptide or protein. Understanding the relationship among the amino acid sequence, the assembly dynamics, and the structure of well ...
The self-assembly of peptides and proteins into higher-ordered structures is encoded in the amino acid sequence of each peptide or protein. Understanding the relationship among the amino acid sequence, the assembly dynamics, and the structure of well-defined peptide oligomers expands the synthetic toolbox for these structures. Here, we present the X-ray crystallographic structure and solution behavior of de novo peptides that form antiparallel coiled-coil hexamers (ACC-Hex) by an interaction motif neither found in nature nor predicted by existing peptide design software. The 1.70 Å X-ray crystallographic structure of peptide 1a shows six α-helices associating in an antiparallel arrangement around a central axis comprising hydrophobic and aromatic residues. Size-exclusion chromatography studies suggest that peptides 1 form stable oligomers in solution, and circular dichroism experiments show that peptides 1 are stable to relatively high temperatures. Small-angle X-ray scattering studies of the solution behavior of peptide 1a indicate an equilibrium of dimers, hexamers, and larger aggregates in solution. The structures presented here represent a new motif of biomolecular self-assembly not previously observed for de novo peptides and suggest supramolecular design principles for material scaffolds based on coiled-coil motifs containing aromatic residues.
Department of Chemistry and Department of Chemical Engineering & Materials Science, University of California, Irvine , Irvine, California 92697-2575, United States.