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Extending a spectrin repeat unit. I: linear force-extension response.

Sterling Paramore·Gary S Ayton·Dina T Mirijanian·Gregory A Voth
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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.

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AlgorithmsAnimalsBiophysicsBrainCarbonChickensComputer SimulationCytoskeletonMagnetic Resonance SpectroscopyMicroscopy, Atomic ForceModels, BiologicalModels, StatisticalMolecular ConformationProtein ConformationProtein DenaturationProtein FoldingProtein Structure, SecondarySoftwareSpectrinThermodynamicsWaterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Sterling Paramore, Gary S Ayton, Dina T Mirijanian, Gregory A Voth. 2005-10-14. Extending a spectrin repeat unit. I: linear force-extension response.. https://doi.org/10.1529/biophysj.105.066969

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