The Structure of Collagen Molecules and Fibrils

Abstract

A systematic examination of molecular models confirms the validity of the three-chain helical structures for collagen recently derived from investigations of polyglycine and poly-L-proline. The cross-sectional molecular symmetry can be simply related to the size and shape of the basic crystallographic cell section of the collagen fibril (a = 62 A, c = 74 A, [beta] = 126[degree] in the moist fibril), whose density is accounted for by inserting 16 molecules per cell.