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PubMed · 8628993

DNA: an extensible molecule.

P Cluzel·A Lebrun·C Heller·R Lavery·J L Viovy·D Chatenay·F Caron
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Abstract

The force-displacement response of a single duplex DNA molecule was measured. The force saturates at a plateau around 70 piconewtons, which ends when the DNA has been stretched about 1.7 times its contour length. This behavior reveals a highly cooperative transition to a state here termed S-DNA. Addition of an intercalator suppresses this transition. Molecular modeling of the process also yields a force plateau and suggests a structure for the extended form. These results may shed light on biological processes involving DNA extension and open the route for mechanical studies on individual molecules in a previously unexplored range.

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Chemical PhenomenaChemistry, PhysicalDNAModels, MolecularNucleic Acid ConformationSoftwareJournal ArticleResearch Support, Non-U.S. Gov't

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P Cluzel, A Lebrun, C Heller, R Lavery, J L Viovy, D Chatenay, F Caron. 1996-02-09. DNA: an extensible molecule.. https://doi.org/10.1126/science.271.5250.792

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