General Solution for Stabilizing Triple Helical Collagen

One of the most ubiquitous stabilizing forces in nature is the hydrogen bond, exemplified by the folded secondary, tertiary, and higher-order structure of biomolecules. Despite the fundamental importance of hydrogen bonding, dependence on this stabilizing force places limitations on nature's proteinogenic building blocks. Herein, we demonstrate that replacement of the strictly conserved glycine in collagen with aza-glycine has profound consequences on the stability and self-assembly of collagen peptides by providing an extra hydrogen bond donor. The additional hydrogen bond provided by aza-glycine allows for complete replacement of glycine residues in collagen peptides and truncation to the smallest self-assembling collagen peptide systems observed to date. Our results highlight the vital importance of hydrogen bonding at desolvated interfaces, providing a new strategy for optimization of designed peptide materials and a general solution for stabilizing the collagen triple helix.