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Updated: Jun 20, 2026
11:42
Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
Line up base pairs and intercalators one by one in a stable duplex
Xingguo Liang1, Toshio Mochizuki, Hidenori Nishioka
1Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan.
Nucleic Acids Symposium Series (2004)
|September 15, 2009
Summary
Researchers created a novel DNA double helix with alternating base pairs and azobenzene molecules. This light-responsive supramolecule can be assembled and disassembled using UV and visible light, paving the way for new nanodevices.
Area of Science:
- Supramolecular chemistry
- Nanotechnology
- Biochemistry
Background:
- DNA nanotechnology enables the creation of complex nanoscale structures.
- Photoresponsive materials offer dynamic control over molecular assembly.
Purpose of the Study:
- To construct a stable DNA-based double helix incorporating azobenzene moieties.
- To develop a photoresponsive supramolecular motif for nanodevice applications.
Main Methods:
- Synthesized modified DNA strands with azobenzene groups.
- Investigated the hybridization of these modified strands to form a double helix.
- Utilized UV and visible light irradiation to control the structure's assembly and disassembly.
Main Results:
- A stable double helix with an interstrand-wedged motif of alternating base pairs and azobenzenes was successfully constructed.
- The DNA-azobenzene supramolecule demonstrated reversible photoresponsive behavior, dismantling under UV light and reforming under visible light.
- The motif featured a precise arrangement: each base pair was flanked by two azobenzenes, and each azobenzene intercalated between two base pairs.
Conclusions:
- A novel photoresponsive DNA-azobenzene supramolecular motif was developed.
- This motif exhibits reversible light-induced assembly and disassembly.
- The findings open possibilities for designing advanced photoresponsive nanostructures and nanodevices.
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