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Direct visualization of supercoiled DNA molecules in solution.

M Adrian·B ten Heggeler-Bordier·W Wahli·A Z Stasiak·A Stasiak·J Dubochet
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Abstract

The shape of supercoiled DNA molecules in solution is directly visualized by cryo-electron microscopy of vitrified samples. We observe that: (i) supercoiled DNA molecules in solution adopt an interwound rather than a toroidal form, (ii) the diameter of the interwound superhelix changes from about 12 nm to 4 nm upon addition of magnesium salt to the solution and (iii) the partition of the linking deficit between twist and writhe can be quantitatively determined for individual molecules.

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DNA, SuperhelicalMagnesium ChlorideNucleic Acid ConformationSolutionsStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov't

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M Adrian, B ten Heggeler-Bordier, W Wahli, A Z Stasiak, A Stasiak, J Dubochet. 1990. Direct visualization of supercoiled DNA molecules in solution.. https://doi.org/10.1002/j.1460-2075.1990.tb07907.x

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