The pulling force of a single DNA molecule condensed by spermidine
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The pulling force of a single DNA molecule condensed by spermidine
In a recent experiment, a single DNA double helix is stretched and relaxed in the presence of spermidine, a short positive polyelectrolyte, and the pulling force is measured as a function of DNA extension. In a certain range of spermidine concentration, a force plateau appears whose value shows maximum as a function of spermidine concentration. We present a quantitative theory of this plateau f...
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In atomic force microscopy-based single molecule force spectroscopy (AFM-SMFS), it is assumed that the pulling angle is negligible and that the force applied to the molecule is equivalent to the force measured by the instrument. Recent studies, however, have indicated that the pulling geometry errors can drastically alter the measured force-extension relationship of molecules. Here we describe ...
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ژورنال
عنوان ژورنال: Physica A: Statistical Mechanics and its Applications
سال: 2005
ISSN: 0378-4371
DOI: 10.1016/j.physa.2004.11.013