Related Experiment Videos
Two-H-bonded and one-H-bonded structure alternations in collagen
J V Milchevsky1, B S Zhorov, N G Esipova
1Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow.
Journal of Biomolecular Structure & Dynamics
|April 27, 1999
Summary
Collagen's conformational variability arises from its primary structure of glycine-X-Y (GXY) tripeptides. A new combined model, alternating one and two hydrogen-bonded structures, explains collagen's 3D structure and improves energy and hydration.
Area of Science:
- Biophysics
- Structural Biology
- Molecular Modeling
Background:
- Collagen's primary structure consists of repeating GXY tripeptides.
- Existing models explain collagen conformations based on amino acid (X) or imino acid (X) substitutions.
- Compound sequences with mixed tripeptide types require a more comprehensive model.
Purpose of the Study:
- To investigate collagen's conformational variability in sequences with mixed tripeptide types.
- To develop and validate a stereochemically sound model for collagen's primary structure.
- To correlate molecular structure with experimental data like hydrogen exchange.
Main Methods:
- Utilized molecular mechanics to analyze junction regions between different structural motifs.
- Considered sequences where two-hydrogen-bonded structures precede one-hydrogen-bonded structures, and vice versa.
- Applied a combined model integrating two-H-bonded and one-H-bonded (Rich & Crick) structures.
Main Results:
- The combined model is stereochemically satisfactory for all typical natural collagen sequences.
- The proposed model offers a more favorable energy profile compared to a continuous one-H-bonded model.
- Enhanced molecular hydration was observed with the combined model.
Conclusions:
- The one-dimensional sequence of collagen dictates its three-dimensional structure.
- The combined model successfully explains collagen's macromolecular structure.
- The model aligns with experimental hydrogen exchange data, supporting its validity.