Kinetics of conformational fluctuations in DNA hairpin-loops.
Proc Natl Acad Sci U S A
; 95(15): 8602-6, 1998 Jul 21.
Article
in En
| MEDLINE
| ID: mdl-9671724
ABSTRACT
The kinetics of DNA hairpin-loop fluctuations has been investigated by using a combination of fluorescence energy transfer and fluorescence correlation spectroscopy. We measure the chemical rates and the activation energies associated with the opening and the closing of the hairpin for different sizes and sequences of the loop and for various salt concentrations. The rate of unzipping of the hairpin stem is essentially independent of the characteristics of the loop, whereas the rate of closing varies greatly with the loop length and sequence. The closing rate scales with the loop length, with an exponent 2.6 +/- 0.3. The closing rate is increased at higher salt concentrations. For hairpin closing, a loop of adenosine repeats leads to smaller rates and higher activation energies than a loop with thymine repeats.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
DNA
/
Nucleic Acid Conformation
Language:
En
Journal:
Proc Natl Acad Sci U S A
Year:
1998
Document type:
Article
Affiliation country:
Estados Unidos