Aza-Glycine Induces Collagen Hyperstability.

Hydrogen bonding is fundamental to life on our planet, and nature utilizes H-bonding in nearly all biomolecular interactions. Often, H-bonding is already maximized in natural biopolymer systems such as nucleic acids, where Watson-Crick H-bonds are fully paired in double-helical structures. Synthetic chemistry allows molecular editing of biopolymers beyond nature's capability. Here we demonstrate that substitution of glycine (Gly) with aza-glycine in collagen may increase the number of interfacial cross-strand H-bonds, leading to hyperstability in the triple-helical form. Gly is the only amino acid that has remained intolerant to substitution in collagen. Our results highlight the vital importance of maximizing H-bonding in higher order biopolymer systems using minimally perturbing alternatives to nature's building blocks.