Volume 81, Number 6, March 2008
|Number of page(s)||5|
|Section||Interdisciplinary Physics and Related Areas of Science and Technology|
|Published online||25 February 2008|
Short-fragment Na-DNA dilute aqueous solutions: Fundamental length scales and screening
Institut za fiziku - HR-10001 Zagreb, Croatia
2 Rudjer Bošković Institute - HR-10001 Zagreb, Croatia
3 Laboratoire de Physique des Solides, Université Paris Sud - F-91405 Orsay, France
4 Department of Physics, University of Ljubljana - SI-1000 Ljubljana, Slovenia
5 J. Stefan Institute - SI-1000 Ljubljana, Slovenia
6 Laboratory of Physical and Structural Biology, NICHD, National Institutes of Health - Bethesda, MD 20892, USA
Corresponding author: email@example.com
Accepted: 28 January 2008
Dielectric spectroscopy is used to investigate fundamental length scales of 146 bp short-fragment (nucleosomal) dilute Na-DNA solutions. Two relaxation modes are detected: the high- and the low-frequency mode. Dependence of the corresponding length scales on the DNA and on the (uni-valent) salt concentration is studied in detail, being different from the case of long, genomic DNA, investigated before. In low-added-salt regime, the length scale of the high-frequency mode scales as the average separation between DNAs, though it is smaller in absolute magnitude, whereas the length scale of the low-frequency mode is equal to the contour length of DNA. These fundamental length scales in low-added-salt regime do not depend on whether DNA is in a double-stranded or single-stranded form. On the other hand, with increasing added salt, the characteristic length scale of the low-frequency mode diminishes at low DNA concentrations probably due to dynamical formation of denaturation bubbles and/or fraying in the vicinity of DNA denaturation threshold.
PACS: 87.15.H- – Dynamics of biomolecules / 82.39.Pj – Nucleic acids, DNA and RNA bases / 77.22.Gm – Dielectric loss and relaxation
© EPLA, 2008
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.