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Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures
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Published on: January 19, 2019

Cationic agents for DNA compaction.

Sylwia Gaweda1, M Carmen Morán, Alberto A C C Pais

  • 1Chemistry Department, Coimbra University, 3004-535 Coimbra, Portugal.

Journal of Colloid and Interface Science
|April 29, 2008
PubMed
Summary
This summary is machine-generated.

Different agents cause T4 DNA to change shape. Lysozyme and protamine sulfate induce a complete coil-to-globule transition, while others result in less compaction.

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11:42

Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes

Published on: November 1, 2012

Area of Science:

  • Molecular Biology
  • Biophysics
  • Materials Science

Background:

  • DNA compaction is crucial for cellular processes and gene packaging.
  • Understanding DNA conformational changes induced by various agents is key to controlling its structure and function.

Purpose of the Study:

  • To investigate the conformational alterations of individual T4 DNA molecules.
  • To compare the efficacy of different compacting agents on DNA structure.
  • To establish a reliable protocol for size estimation in DNA compaction studies.

Main Methods:

  • Fluorescence microscopy was employed to visualize and analyze individual T4 DNA molecule conformations.
  • A range of compacting agents were tested, including cationic surfactants (CTAB, CTAC), iron(III), lysozyme, and protamine sulfate.
  • Dynamic light scattering experiments were performed to validate size estimates obtained from microscopy.

Main Results:

  • Lysozyme and protamine sulfate induced a significant coil-to-globule transition, indicative of a first-order phase transition.
  • Iron(III) and CTAB/CTAC resulted in a lower maximum degree of DNA compaction, with intermediate structures observed.
  • A protocol for reproducible size estimation using fluorescence microscopy was proposed.

Conclusions:

  • The choice of compacting agent critically influences the extent and nature of T4 DNA conformational changes.
  • Lysozyme and protamine sulfate are effective in inducing globule formation, while other agents lead to partial compaction.
  • The study provides insights into DNA structural transitions and offers a method for reliable size estimation.