Dataset Information

Stabilization and anomalous hydration of collagen fibril under heating.

ABSTRACT:

Background

Type I collagen is the most common protein among higher vertebrates. It forms the basis of fibrous connective tissues (tendon, chord, skin, bones) and ensures mechanical stability and strength of these tissues. It is known, however, that separate triple-helical collagen macromolecules are unstable at physiological temperatures. We want to understand the mechanism of collagen stability at the intermolecular level. To this end, we study the collagen fibril, an intermediate level in the collagen hierarchy between triple-helical macromolecule and tendon.

Methodology/principal finding

When heating a native fibril sample, its Young's modulus decreases in temperature range 20-58°C due to partial denaturation of triple-helices, but it is approximately constant at 58-75°C, because of stabilization by inter-molecular interactions. The stabilization temperature range 58-75°C has two further important features: here the fibril absorbs water under heating and the internal friction displays a peak. We relate these experimental findings to restructuring of collagen triple-helices in fibril. A theoretical description of the experimental results is provided via a generalization of the standard Zimm-Bragg model for the helix-coil transition. It takes into account intermolecular interactions of collagen triple-helices in fibril and describes water adsorption via the Langmuir mechanism.

Conclusion/significance

We uncovered an inter-molecular mechanism that stabilizes the fibril made of unstable collagen macromolecules. This mechanism can be relevant for explaining stability of collagen.

SUBMITTER: Gevorkian SG

PROVIDER: S-EPMC3823754 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Publications

Stabilization and anomalous hydration of collagen fibril under heating.

Gevorkian Sasun G SG Allahverdyan Armen E AE Gevorgyan David S DS Simonian Aleksandr L AL Hu Chin-Kun CK

PloS one 20131111 11

<h4>Background</h4>Type I collagen is the most common protein among higher vertebrates. It forms the basis of fibrous connective tissues (tendon, chord, skin, bones) and ensures mechanical stability and strength of these tissues. It is known, however, that separate triple-helical collagen macromolecules are unstable at physiological temperatures. We want to understand the mechanism of collagen stability at the intermolecular level. To this end, we study the collagen fibril, an intermediate level ...[more]

PMID: 24244320

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Dataset Information

Stabilization and anomalous hydration of collagen fibril under heating.

Background

Methodology/principal finding

Conclusion/significance

Publications

Stabilization and anomalous hydration of collagen fibril under heating.

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