Related Experiment Video
Updated: May 10, 2026
10:01
Combining Chemical Cross-linking and Mass Spectrometry of Intact Protein Complexes to Study the Architecture of Multi-subunit Protein Assemblies
Published on: November 28, 2017
The effect of cross-link distributions in axially-ordered, cross-linked networks
C Brad Bennett1, James Kruczek, D A Rabson
1Department of Physics, University of South Florida, Tampa, FL 33620, USA.
Summary
Cross-linking in biopolymers like collagen affects material properties. This study models how distinct cross-link arrangements influence denaturation transitions, suggesting a key role for site arrangement in collagen
Area of Science:
- Biophysics
- Materials Science
- Polymer Chemistry
Background:
- Cross-linking significantly alters biopolymer material properties, including melting temperature.
- Fibrillar collagen, an ordered network of cross-linked chains, shows a broadened denaturation transition.
- This transition broadening is often attributed to the sequential denaturation of multiple species.
Purpose of the Study:
- To model axially-ordered, cross-linked materials using stiff chains with defined cross-link site arrangements.
- To investigate the impact of identical versus distinct cross-link site arrangements on material behavior.
- To explore the contribution of cross-link site arrangement to the denaturation transition broadening in fibrillar collagen.
Main Methods:
- Development of a computational model for axially-ordered, cross-linked materials.
- Simulations of systems with identical arrangements of cross-link-forming sites.
- Simulations of systems with non-identical arrangements of cross-link-forming sites.
Main Results:
- Systems with identical cross-link site arrangements exhibit critical behavior.
- Systems with non-identical cross-link site arrangements demonstrate a crossover.
- The arrangement of cross-link-forming sites is shown to influence the denaturation transition.
Conclusions:
- The model provides insights into the behavior of cross-linked materials.
- Distinct arrangements of cross-link-forming sites lead to crossover behavior.
- The spatial arrangement of cross-links is a potential factor in the broadened denaturation transition observed in fibrillar collagen.
Related Concept Videos
01:16Eccentric Axial Loading in a Plane of Symmetry
Eccentric axial loading occurs when an axial load is applied away from the centroidal axis of a structural member. This scenario is common in engineering, where structural elements may not be directly aligned due to various design or functional requirements.
00:49Ligand Binding and Linkage
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence the...
01:11Formation of Higher-order Actin Filaments
The polymerization of G-actin monomers into filamentous F-actin is a multi-step process. Once the F-actins are formed, they can bundle together in different arrangements to form higher-order networks and regulate cellular functions. Common examples include the formation of lamellipodia and filopodia at the cell's leading edge by actin reorganization in a migrating cell. The microvilli on the brush border epithelial cells are also formed through the F-actin network.
The high-order actin networks...
The high-order actin networks...
01:16Torsion of Noncircular Members
Circular shafts undergoing torsional stress maintain their cross-sectional integrity due to their axisymmetric nature. This symmetry ensures an even distribution of stress, allowing the shaft to withstand torsion without distorting. In contrast, square bars, lacking this axial symmetry, experience significant distortion across their cross-sections when subjected to torsion, with the exception of along their diagonals and at lines connecting midpoints. A detailed examination of a cubic element...
01:15Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
01:24Determination of Molar Masses of Polymers I
Polymerization produces macromolecules with a range of chain lengths due to the random nature of molecular growth processes. As chains form and terminate at different stages, a single polymer sample contains molecules of varying sizes rather than a uniform structure. This variability is described using average molar masses and distribution-related parameters, which together provide a comprehensive understanding of polymer characteristics.The distribution of molar masses plays a critical role in...