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PubMed · 12689326

Bubble dynamics in double-stranded DNA.

Grégoire Altan-Bonnet·Albert Libchaber·Oleg Krichevsky
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Abstract

We report the first measurement of the dynamics of bubble formation in double-stranded DNA. Fluctuations of fluorescence of a synthetic DNA construct, internally tagged with a fluorophore and a quencher, are monitored by fluorescence correlation spectroscopy. The relaxation dynamics follow a multistate relaxation kinetics, with a characteristic time scale of 50 microseconds. A simple model of bubble dynamics based on constant zipping-unzipping rates is proposed to account for our experimental data. The role of different secondary structures stabilizing the open bubble is tested.

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DNAFluorescenceFluorescent DyesKineticsNucleic Acid ConformationSpectrometry, FluorescenceTemperatureThermodynamicsJournal ArticleResearch Support, Non-U.S. Gov't

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Grégoire Altan-Bonnet, Albert Libchaber, Oleg Krichevsky. 2003-04-01. Bubble dynamics in double-stranded DNA.. https://doi.org/10.1103/physrevlett.90.138101

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