Supercoiling DNA Locates Mismatches.
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ABSTRACT:
SUBMITTER: Dittmore A
PROVIDER: S-EPMC5661871 | biostudies-literature | 2017 Oct
REPOSITORIES: biostudies-literature
Publications
Supercoiling DNA Locates Mismatches.
Dittmore Andrew A Brahmachari Sumitabha S Takagi Yasuharu Y Marko John F JF Neuman Keir C KC
Physical review letters 20171003 14
We present a method of detecting sequence defects by supercoiling DNA with magnetic tweezers. The method is sensitive to a single mismatched base pair in a DNA sequence of several thousand base pairs. We systematically compare DNA molecules with 0 to 16 adjacent mismatches at 1 M monovalent salt and 3.6 pN force and show that under these conditions, a single plectoneme forms and is stably pinned at the defect. We use these measurements to estimate the energy and degree of end-loop kinking at def ...[more]
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