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PubMed · 1739738

Parallel stranded DNA under the scanning tunnelling microscope.

J D Zhu·M Q Li·L Z Xiu·J Q Zhu·J Hu·M M Gu·Y L Xu·L P Zhang·Z Q Huang·B K Chernov
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Abstract

Using scanning tunnelling microscopy, we have directly observed parallel stranded DNA helixes of 43 nucleotides in length. The double helix is right-handed and has an average spacing, 17.43 A (+/- 1 S.D.: 2.30 A), and an average apparent depth, 4.79 A (+/- 1 S.D.: 1.04 A) for each groove. The average pitch of the helical turn is 34 A (+/- 1 S.D.: 3.35 A) and consists of no more than ten base pairs. The diameter of the helix is approx. 17-20 A. Our results provide direct evidence for the existence of a parallel structure of DNA in vitro and some details of its fine structure.

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Base SequenceChemical PhenomenaChemistry, PhysicalDNAMicroscopy, Scanning TunnelingMolecular Sequence DataNucleic Acid ConformationJournal ArticleResearch Support, Non-U.S. Gov't

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J D Zhu, M Q Li, L Z Xiu, J Q Zhu, J Hu, M M Gu, Y L Xu, L P Zhang, Z Q Huang, B K Chernov. 1992-01-23. Parallel stranded DNA under the scanning tunnelling microscope.. https://pubmed.ncbi.nlm.nih.gov/1739738/

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