2g66

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spinqualitylabelsall models 2g66, resolution 1.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal structure of a collagen-like peptide with 3(S)Hyp in the Xaa position

Overview

Collagen has a triple helical structure comprising strands with a, repeating Xaa-Yaa-Gly sequence. L-Proline (Pro) and, 4(R)-hydroxyl-L-proline (4(R)Hyp) residues are found most frequently in, the Xaa and Yaa positions. However, in natural collagen, 3(S)-hydroxyl-L-proline (3(S)Hyp) occurs in the Xaa positions to varying, extents and is most common in collagen types IV and V. Although 4(R)Hyp, residues in the Yaa positions have been shown to be critical for the, formation of a stable triple helix, the role of 3(S)Hyp residues in the, Xaa position is not well understood. Indeed, recent studies have, demonstrated that the presence of 3(S)Hyp in the Xaa positions of, collagen-like peptides actually has a destabilizing effect relative to, peptides with Pro in these locations. Whether this destabilization is, reflected in a local unfolding or in other structural alterations of the, collagen triple helix is unknown. Thus, to determine what effect the, presence of 3(S)Hyp residues in the Xaa positions has on the overall, conformation of the collagen triple helix, we determined the crystal, structure of the polypeptide, H-(Gly-Pro-4(R)Hyp)3-(Gly-3(S)Hyp-4(R)Hyp)2-(Gly-Pro-4(R)Hyp)4-OH to 1.80, A resolution. The structure shows that, despite the presence of the, 3(S)Hyp residues, the peptide still adopts a typical 7/2 superhelical, symmetry similar to that observed in other collagen structures. The, puckering of the Xaa position 3(S)Hyp residues, which are all down, (Cgamma-endo), and the varphi/psi dihedral angles of the Xaa 3(S)Hyp, residues are also similar to those of typical collagen Pro Xaa residues., Thus, the presence of 3(S)Hyp in the Xaa positions does not lead to large, structural alterations in the collagen triple helix.

About this Structure

2G66 is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.

Reference

The crystal structure of a collagen-like polypeptide with 3(S)-hydroxyproline residues in the Xaa position forms a standard 7/2 collagen triple helix., Schumacher MA, Mizuno K, Bachinger HP, J Biol Chem. 2006 Sep 15;281(37):27566-74. Epub 2006 Jun 23. PMID:16798737

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