Structurally Homogeneous Nanosheets from Self‐Assembly of a Collagen‐Mimetic Peptide

Abstract

A collagen‐mimetic peptide, NSIII, has been designed with three sequential blocks having positive, neutral, and negative charges, respectively. The non‐canonical imino acid, (2S,4S)‐4‐aminoproline (amp), was used to specify the positive charges at the Xaa positions of (Xaa‐Yaa‐Gly) triads in the N‐terminal domain of NSIII. Peptide NSIII underwent self‐assembly from aqueous solution to form a highly homogeneous population of nanosheets. Two‐dimensional crystalline sheets formed in which the length of the peptide defined the height of the sheets. These results contrasted with prior results on a similar multi‐domain collagen‐mimetic polypeptides in which the sheets had highly polydisperse distribution of sizes in the (x/y)‐ and (z)‐dimensions. The structural differences between the two nanosheet assemblies were interpreted in terms of the relative stereoelectronic effects of the different aminoproline derivatives on the local triple helical conformation of the peptides.

Peptide tessellation yields micrometre-scale collagen triple helices

“…, an xy - and a yx -template) could produce sets of CMPs that assemble independently, even when mixed. In theory, elements that allow the programmed association of triple helices 35,36 can also be encoded into CMPs. Our current work enables us to produce “human-scale” triple-helices.…”

A Single Stereodynamic Center Modulates the Rate of Self‐Assembly in a Biomolecular System

“…Over the past several decades, collagen has been the focus of many research efforts aimed at developing a molecular level understanding of its self-assembly properties and for the development of designed materials. [11,12] The most common repeating amino acid motif is XaaYaaGly, where Xaa is proline 28% of the time and Yaa is either hydroxyproline or proline 38% of the time with the Glycine remaining intolerant to substitution. 10c To date, nearly all amino acid substitutions have lead to significant destabilization of the collagen triple helix except a few rare examples.…”