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Updated: Aug 19, 2026

DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
Intradimerically tethered DNA topoisomerase II is catalytically active in DNA transport
1Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, 84132, USA.
Abstract:
A covalently cross-linked dimer of yeast DNA topoisomerase II was created by fusing the enzyme with the GCN4 leucine zipper followed by two glycines and a cysteine. Upon oxidation of the chimeric protein, a disulfide bond forms between the two carboxyl termini, covalently and intradimerically cross-linking the two protomers. In addition, all nine of the cysteines naturally occurring in topoisomerase II have been changed to alanines in this construct. This cross-linked, cysteine-less topoisomerase II is catalytically active in DNA duplex passage as indicated by ATP-dependent DNA supercoil relaxation and kinetoplast DNA decatenation assays. However, these experiments do not directly distinguish between a "one-gate" and a "two-gate" mechanism for the enzyme.
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