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Updated: May 9, 2026

Visualization of UV-induced Replication Intermediates in E. coli using Two-dimensional Agarose-gel Analysis
Published on: December 21, 2010
Plasmid DNA topology assayed by two-dimensional agarose gel electrophoresis
Jorge B Schvartzman1, María-Luisa Martínez-Robles, Pablo Hernández
1Department of Cell and Molecular Biology, Centro de Investigaciones Biológicas (CSIC), Madrid, Spain.
Abstract:
Two-dimensional (2D) agarose gel electrophoresis is nowadays one of the best methods available to analyze DNA molecules with different masses and shapes. The possibility to use nicking enzymes and intercalating agents to change the twist of DNA during only one or in both runs, improves the capacity of 2D gels to discern molecules that apparently may look alike. Here we present protocols where 2D gels are used to understand the structure of DNA molecules and its dynamics in living cells. This knowledge is essential to comprehend how DNA topology affects and is affected by all the essential functions that DNA is involved in: replication, transcription, repair and recombination.
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