Molecular and fibrillar structures of collagen

Abstract

The triple helix is a specialized protein motif found in all collagens. The molecular conformation of the collagen-helix confers strict amino acid sequence constraints requiring a Glycine at every third position and a high content of imino acid. Although the X-ray diffraction pattern of fibrous collagen has been studied since the 1920s, deficiencies in the diffraction data have prevented efforts to obtain the unique helical model from the fiber diffraction pattern only. On the other hand, during the past 15 years, many single crystal analyses of collagen model peptides provide various important physicochemical information, including average helical symmetry, the presence of hydrogen bond networks, distribution of water molecules, and structural bases of stabilization of a triple helix induced by hydroxyproline. ©2010, The Society of Polymer Science.