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11:27
Studying DNA Looping by Single-Molecule FRET
Published on: June 28, 2014
Conformational dependence of DNA ballistic conductivity
E B Starikov1, A Quintilla, K H Lee
1Forschungszentrum Karlsruhe, Institut fur Nanotechnologie, P. O. Box 3640, D-76021 Karlsruhe, Germany.
The Journal of Chemical Physics
|December 3, 2008
Summary
DNA conformation dramatically impacts its electrical conductivity, especially during the B-to-Z transition. This finding, using the atomistic Kubo-Verges method, could lead to high-density DNA memory devices.
Area of Science:
- * Molecular Biophysics
- * Nanotechnology
- * Computational Chemistry
Background:
- * DNA exists in various conformations (A, B, Z) affecting its properties.
- * Understanding DNA's electronic transport is crucial for molecular electronics.
- * Previous studies have explored DNA conductivity with varying theoretical approaches.
Purpose of the Study:
- * To calculate the ballistic conductance of different DNA conformations.
- * To investigate the influence of DNA structure on valence band conductivity.
- * To explore the potential of DNA conformational switching for memory devices.
Main Methods:
- * Atomistic Kubo-Verges method for ballistic conductance calculation.
- * Utilization of experimental DNA structures and model complexes.
- * Simulation of DNA in vacuum and with explicit molecular dynamics (MD) and water-counterion environments.
Main Results:
- * Significant variations in valence band conductivity were observed across A, B, and Z DNA conformations.
- * The B-to-Z DNA transition showed the most dramatic conductivity changes.
- * Trimethylthiol linkers had minimal impact on conductivity differences in vacuum.
- * Water-counterion environments significantly reduced conductivity differences between B- and Z-DNA.
Conclusions:
- * DNA conformation is a critical determinant of its electrical conductivity.
- * Conformational switching induced by electric fields offers potential for DNA-based memory devices.
- * The influence of the surrounding environment on DNA conductivity is substantial.
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