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Updated: Mar 17, 2026

Simple and Fast Rolling Circle Amplification-Based Detection of Topoisomerase 1 Activity in Crude Biological Samples
Published on: December 2, 2022
Characterization of molecular interactions between Escherichia coli RNA polymerase and topoisomerase I by molecular
Purushottam B Tiwari1, Prem P Chapagain2,3, Srikanth Banda3,4
1Department of Oncology, Georgetown University, Washington, DC, USA.
Abstract:
Escherichia coli topoisomerase I (EctopoI), a type IA DNA topoisomerase, relaxes the negative DNA supercoiling generated by RNA polymerase (RNAP) during transcription elongation. Due to the lack of structural information on the complex, the exact nature of the RNAP-EctopoI interactions remains unresolved. Herein, we report for the first time, the structure-based modeling of the RNAP-EctopoI interactions using computational methods. Our results predict that the salt bridge as well as hydrogen bond interactions are responsible for the formation and stabilization of the RNAP-EctopoI complex. Our investigations provide molecular insights for understanding how EctopoI interacts with RNAP, a critical step for preventing hypernegative DNA supercoiling during transcription.
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