Quasi-hexagonal molecular packing in collagen fibrils

@article{Hulmes1979QuasihexagonalMP,
  title={Quasi-hexagonal molecular packing in collagen fibrils},
  author={David J S Hulmes and Andrew D. Miller},
  journal={Nature},
  year={1979},
  volume={282},
  pages={878-880}
}
Collagen molecules in native 66.8 nm (D) periodic fibrils are widely believed to be assembled into discrete, rope-like sub-structures, or microfibrils1–17. Several types of microfibril have been proposed (2,4,5,7- and 8-stranded), mainly on the basis of information contained in the medium angle X-ray diffraction patterns of native tendon fibres1,5–7. These patterns show a series of equatorial and near-equatorial Bragg reflections which indicate that the collagen molecules are arranged on a… 
A new model for packing of type-I collagen molecules in the native fibril
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TLDR
The lateral packing of a collagen‐like molecule, CH3CO‐(Gly‐L‐Pro‐ L‐Pro)4‐NHCH3, has been examined by energy minimization with the ECEPP/3 force field and is found to be energetically more favorable than the Smith microfibril model.
Molecular packing in type I collagen fibrils.
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