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Updated: Jun 23, 2026

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CD Spectroscopy to Study DNA-Protein Interactions
Published on: February 10, 2022
Circular dichroism for the analysis of protein-DNA interactions
1Biophysics Laboratories, Institute of Biomedical and Biomolecular Science, St. Michael's Building, University of Portsmouth, Portsmouth PO1 2DT, UK.
Methods in Molecular Biology (Clifton, N.J.)
|April 21, 2009
Abstract:
Circular dichroism (CD) is a well-established technique for the analysis of both protein and DNA structure. The analysis of protein-nucleic acid complexes presents greater challenges, but at wavelengths above 250 nm, the circular dichroism signal from the DNA predominates. Examples are given of the use of CD to examine structural changes to DNA induced by protein binding.
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