Sequence-specific response of collagen-mimetic peptides to osmotic pressure

Abstract Native collagen molecules usually contract upon dehydration, but the details of their interaction with water are poorly understood. Previous molecular modeling studies indicated a spatially inhomogeneous response, combination local axial expansion and contraction. Such sequence-dependent effects difficult to study native collagen. In this article, we use collagen-mimetic peptides (CMPs) investigate effect osmotic pressure on several sequences. Synchrotron x-ray diffraction combined dynamics simulations shows that CMPs pack differently depending exhibit changes in helical rise per residue individual molecules. Infrared spectroscopy reveals affects stability triple helix through helix-stabilizing hydrogen bonds. Surprisingly, canonical sequence glycine–proline–hydroxyproline found elongate while modifications able reverse tendency. This strongly suggests overall contraction is not programmed into specific amino acids substitute for proline or hydroxyproline along protein chain. Collagen an essential mammalian extracellular tissues better understanding its mechanical function important both from materials science biomedical viewpoint. Recently, has been shown fibre direction when subjected stress, process could play roles strengthening bone developing tissue tension during matrix development. The present work uses collagen-like short show responsible conclusion acid must have evolved include guest sequences within glycine-proline-hydroxyproline repeat provide observed contractility. Impact statement Graphic