Results 11 to 20 of about 9,967 (240)

Structural basis of gate-DNA breakage and resealing by type II topoisomerases. [PDF]

PLoS ONE, 2010
Type II DNA topoisomerases are ubiquitous enzymes with essential functions in DNA replication, recombination and transcription. They change DNA topology by forming a transient covalent cleavage complex with a gate-DNA duplex that allows transport of a ...
Ivan Laponogov, Xiao-Su Pan, Dennis A Veselkov, Katherine E McAuley, L Mark Fisher, Mark R Sanderson   +5 more
doaj   +6 more sources

Mechanism of topology simplification by type II DNA topoisomerases [PDF]

Proceedings of the National Academy of Sciences, 2001
Type II DNA topoisomerases actively reduce the fractions of knotted and catenated circular DNA below thermodynamic equilibrium values. To explain this surprising finding, we designed a model in which topoisomerases introduce a sharp bend in DNA. Because the enzymes have a specific orientation relative to the bend, they act like Maxwell's demon ...
A V, Vologodskii, W, Zhang, V V, Rybenkov, A A, Podtelezhnikov, D, Subramanian, J D, Griffith, N R, Cozzarelli   +6 more
openaire   +4 more sources

DNA-Topology Simplification by Topoisomerases

Molecules, 2021
The topological properties of DNA molecules, supercoiling, knotting, and catenation, are intimately connected with essential biological processes, such as gene expression, replication, recombination, and chromosome segregation. Non-trivial DNA topologies
Andreas Hanke, Riccardo Ziraldo, Stephen D. Levene   +2 more
doaj   +3 more sources

Supercoiled DNA recognition and cleavage control in topoisomerase VI [PDF]

Nature Communications
Type II topoisomerases modulate DNA supercoiling and resolve chromosome entanglements. Type IIB topoisomerases, exemplified by DNA topoisomerase VI (Top6), are used by plants and archaea to support endoreduplication and cell proliferation, respectively ...
Daniel E. Richman, Timothy J. Wendorff, Fahad Rashid, Curtis Beck, Qianyun Yan, Haley R. Johnson, Ryan A. Eckerty, Jonathan M. Fogg, Matthew L. Baker, Lynn Zechiedrich, James M. Berger   +10 more
doaj   +2 more sources

Alignment and phylogenetic analysis of type II DNA topoisomerases [PDF]

Journal of Biosciences, 1996
DNA topoisomerases have been evolved to solve the topological problems of DNA during replication, transcription, recombination and segregation. Discovery of several new enzymes and their characterization has necessitated this compilation. This analysis shows the distinct evolutionary relatedness of type II DNA topoisomerases.
Madhusudan, K, Nagaraja, V
core   +5 more sources

DNA binding and cleavage mechanism of DNA topoisomerase VI, an evolutionary counterpart of Spo11/Wadjet/Gabija systems [PDF]

Structural Dynamics
Type II topoisomerases resolve DNA supercoiling and chromosome entanglements. Type IIB topoisomerases, exemplified by Top6, are used by plants and archaea to support endoreduplication and cell proliferation, respectively; homologs of Top6 subunits ...
Daniel E Richman, Timothy J Wendorff, Fahad Rashid, Curtis Beck, Matthew L Baker, Jonathan M Fogg, Lynn Zechiedrich, James M Berger   +7 more
doaj   +2 more sources

Two-Dimensional Gel Electrophoresis to Study the Activity of Type IIA Topoisomerases on Plasmid Replication Intermediates [PDF]

Biology, 2021
DNA topoisomerases are the enzymes that regulate DNA topology in all living cells. Since the discovery and purification of ω (omega), when the first were topoisomerase identified, the function of many topoisomerases has been examined.
Jorge Cebrián, Victor Martínez, Pablo Hernández, Dora B. Krimer, María-José Fernández-Nestosa, Jorge B. Schvartzman   +5 more
doaj   +2 more sources

Inhibition of Zn(II) binding type IA topoisomerases by organomercury compounds and Hg(II). [PDF]

PLoS ONE, 2015
Type IA topoisomerase activities are essential for resolving DNA topological barriers via an enzyme-mediated transient single strand DNA break. Accumulation of topoisomerase DNA cleavage product can lead to cell death or genomic rearrangement.
Bokun Cheng, Thirunavukkarasu Annamalai, Shayna Sandhaus, Priyanka Bansod, Yuk-Ching Tse-Dinh   +4 more
doaj   +3 more sources

Conversion of DNA gyrase into a conventional type II topoisomerase [PDF]

Proceedings of the National Academy of Sciences, 1996
DNA gyrase is unique among topoisomerases in its ability to introduce negative supercoils into closed-circular DNA. We have demonstrated that deletion of the C-terminal DNA-binding domain of the A subunit of gyrase gives rise to an enzyme that cannot supercoil DNA but relaxes DNA in an ATP-dependent manner.
Kampranis, S C, Maxwell, A
openaire   +3 more sources

Tightening of DNA knots by supercoiling facilitates their unknotting by type II DNA topoisomerases [PDF]

Proceedings of the National Academy of Sciences, 2011
Using numerical simulations, we compare properties of knotted DNA molecules that are either torsionally relaxed or supercoiled. We observe that DNA supercoiling tightens knotted portions of DNA molecules and accentuates the difference in curvature between knotted and unknotted regions. The increased curvature of knotted regions is expected to make them
Witz G, Dietler G, Stasiak A
openaire   +6 more sources