Terminal aspartic acids promote the self-assembly of collagen mimic peptides into nanospheres

Abstract

The development of novel strategies to construct collagen mimetic peptides capable of self-assembling into higher-order structures plays a critical role in the discovery of functional biomaterials. We herein report the construction of a novel type of amphiphile-like peptide conjugating the repetitive triple helical (GPO)_m sequences characteristic of collagen with terminal hydrophilic aspartic acids. The amphiphile-like collagen mimic peptides containing a variable length of (Gly-Pro-Hyp)_m sequences consistently generate well-ordered nanospherical supramolecular structures. The C-terminal aspartic acids have been revealed to play a determinant role in the appropriate self-assembly of amphiphile-like collagen mimic peptides. Their presence is a prerequisite for self-assembly, and their lengths could modulate the morphology of final assemblies. We have demonstrated for the first time that amphiphile-like collagen mimic peptides with terminal aspartic acids may provide a general and convenient strategy to create well-defined nanostructures in addition to amphiphile-like peptides utilizing β-sheet or α-helical coiled-coil motifs. The newly developed assembly strategy together with the ubiquitous natural function of collagen may lead to the generation of novel improved biomaterials.