Title | Extending a Spectrin Repeat Unit. I: Linear Force-Extension Response |
Publication Type | Journal Article |
Year of Publication | 2006 |
Authors | Paramore, S, Ayton, GS, Mirijanian, DT, Voth, GA |
Journal | Biophys J |
Volume | 90 |
Pagination | 92-100 |
Keywords | Algorithms Animals Biophysics/*methods Brain/metabolism Carbon/chemistry Chickens Computer Simulation Cytoskeleton/chemistry Magnetic Resonance Spectroscopy Microscopy, Atomic Force/methods Models, Biological Models, Secondary Software Spectrin/*chemistry/metabolism Thermodynamics Water/chemistry, Statistical Molecular Conformation Protein Conformation Protein Denaturation Protein Folding Protein Structure |
Abstract | Nonequilibrium molecular dynamics simulations were used to calculate the elastic properties of a spectrin repeat unit. A contiguous alpha-helical linker was constructed by employing periodic boundary conditions, allowing a novel scheme for evaluating the thermodynamic force as a function of extension. By measuring the force-extension response under small extensions, spectrin was observed to behave primarily as an elastic material with a spring constant of 1700 +/- 100 pN/nm. The implications of this spring constant, in terms of the properties of the spectrin tetramer, are also discussed. |
DOI | 10.1529/biophysj.105.066969 |