Abstract:
:The spermine-induced DNA condensation is a first-order phase transition. Here, we apply a novel technique fluorescence lifetime correlation spectroscopy to analyze this transition in a greater detail. We show that the method allows for the observation of the condensed and uncondensed molecules simultaneously based solely on different fluorescence lifetimes of the intercalating fluorophore PicoGreen in the folded und unfolded domains of DNA. The auto- and cross-correlation functions reveal that a small fraction of the DNA molecules is involved in the dynamic intramolecular equilibrium. Careful inspection of the cross-correlation curves suggests that folding occurs gradually within milliseconds.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Humpolícková J,Benda A,Sýkora J,Machán R,Kral T,Gasinska B,Enderlein J,Hof Mdoi
10.1529/biophysj.107.122408subject
Has Abstractpub_date
2008-02-01 00:00:00pages
L17-9issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(08)70671-4journal_volume
94pub_type
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