DNA Supercoiling Measurement in Bacteria

  • Yingting Liu
  • Zhi-Chun Hua
  • Fenfei LengEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1703)


DNA supercoiling plays critical roles in several essential DNA metabolic pathways, such as replication, transcription and recombination. Typically plasmid DNA molecules are used to measure DNA supercoiling status inside bacterial cells. In this chapter, we describe how to isolate plasmid DNA molecules from E. coli cells and determine DNA supercoiling density by 1% agarose gel electrophoresis containing chloroquine using plasmid pACYC184 as an example.

Key words

Agarose gel electrophoresis DNA supercoiling DNA topoisomers Supercoiling density 


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Copyright information

© Springer Science+Business Media, LLC 2018

Authors and Affiliations

  1. 1.Biomolecular Sciences InstituteFlorida International UniversityMiamiUSA
  2. 2.Department of Chemistry & BiochemistryFlorida International UniversityMiamiUSA
  3. 3.School of Life SciencesNanjing UniversityNanjingChina
  4. 4.Changzhou High-Tech Research Institute of Nanjing University and Jiangsu TargetPharma Laboratories Inc.ChangzhouChina

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