Rolling-circle amplification under topological constraints
Related Experiment Video
Updated: Oct 3, 2026

Simple and Fast Rolling Circle Amplification-Based Detection of Topoisomerase 1 Activity in Crude Biological Samples
Published on: December 2, 2022
Heiko Kuhn1, Vadim V Demidov, Maxim D Frank-Kamenetskii
1Center for Advanced Biotechnology, Department of Biomedical Engineering, Boston University, 36 Cummington Street, Boston, MA 02215, USA.
Abstract:
We have performed rolling-circle amplification (RCA) reactions on three DNA templates that differ distinctly in their topology: an unlinked DNA circle, a linked DNA circle within a pseudorotaxane-type structure and a linked DNA circle within a catenane. In the linked templates, the single-stranded circle (dubbed earring probe) is threaded, with the aid of two peptide nucleic acid openers, between the two strands of double-stranded DNA (dsDNA). We have found that the RCA efficiency of amplification was essentially unaffected when the linked templates were employed. By showing that the DNA catenane remains intact after RCA reactions, we prove that certain DNA polymerases can carry out the replicative synthesis under topological constraints allowing detection of several hundred copies of a dsDNA marker without DNA denaturation. Our finding may have practical implications in the area of DNA diagnostics.
Related Concept Videos
Rolle’s Theorem
Plastic Deformation in Circular Shafts
Deformation in a Circular Shaft
Dynamics of Circular Motion
Any acceleration must be produced by some force. Therefore, any force or combination of forces can cause centripetal acceleration. A few examples include the tension in the rope on a...
Torsion of Noncircular Members
Rolling Resistance: Problem Solving
