3B0S

Crystal Structure of (Gly-Pro-Hyp)9

Summary for 3B0S

• Entry DOI: 10.2210/pdb3b0s/pdb
• Related: 1V4F 1V7H 3AH9
• Descriptor: collagen-like peptide (2 entities in total)
• Functional Keywords: collagen, triple helix, structural protein
• Total number of polymer chains: 6
• Total formula weight: 14541.28

Authors

Okuyama, K.,Miyama, K.,Mizuno, K.,Bachinger, H.P. (deposition date: 2011-06-14, release date: 2012-05-30, Last modification date: 2023-11-01)

Primary citation

Okuyama, K.,Miyama, K.,Mizuno, K.,Bachinger, H.P.
Crystal structure of (Gly-Pro-Hyp)(9) : Implications for the collagen molecular model.
Biopolymers, 97:607-616, 2012

PubMed Abstract: Collagens have long been believed to adopt a triple-stranded molecular structure with a 10/3 symmetry (ten triplet units in three turns) and an axial repeat of 29 Å. This belief even persisted after an alternative structure with a 7/2 symmetry (seven triplet units in two turns) with an axial repeat of 20 Å had been proposed. The uncertainty regarding the helical symmetry of collagens is attributed to inadequate X-ray fiber diffraction data. Therefore, for better understanding of the collagen helix, single-crystal analyses of peptides with simplified characteristic amino acid sequences and similar compositions to collagens have long been awaited. Here we report the crystal structure of (Gly-Pro-Hyp)(9) peptide at a resolution of 1.45 Å. The repeating unit of this peptide, Gly-Pro-Hyp, is the most typical sequence present in collagens, and it has been used as a basic repeating unit in fiber diffraction analyses of collagen. The (Gly-Pro-Hyp)(9) peptide adopts a triple-stranded structure with an average helical symmetry close to the ideal 7/2 helical model for collagen. This observation strongly suggests that the average molecular structure of collagen is not the accepted Rich and Crick 10/3 helical model but is a 7/2 helical conformation.

PubMed: 22605552
DOI: 10.1002/bip.22048

Experimental method

X-RAY DIFFRACTION (1.45 Å)