A Type I DNA Topoisomerase from Trypanosoma cruzi [PDF]
European Journal of Biochemistry, 1983 A type I DNA topoisomerase has been isolated from the nuclei of the flagellate Trypanosoma cruzi, using poly(ethylene glycol) fractionation and chromatography on hydroxyapatite and on phosphocellulose. The relaxation activity was ATP‐independent, enhanced by Mg2+ and spermidine. The enzyme removed supercoils from negative and positive superhelical DNAs.
G F, Riou +4 more
openaire +2 more sources
55.2, a phage T4 ORFan gene, encodes an inhibitor of Escherichia coli topoisomerase I and increases phage fitness. [PDF]
PLoS ONE, 2015 Topoisomerases are enzymes that alter the topological properties of DNA. Phage T4 encodes its own topoisomerase but it can also utilize host-encoded topoisomerases. Here we characterized 55.2, a phage T4 predicted ORF of unknown function.
Yves Mattenberger +2 more
doaj +1 more source
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 +4 more
doaj +1 more source
Two type I topoisomerases maintain DNA topology in human mitochondria
Nucleic Acids Research, 2022 Abstract Genetic processes require the activity of multiple topoisomerases, essential enzymes that remove topological tension and intermolecular linkages in DNA. We have investigated the subcellular localisation and activity of the six human topoisomerases with a view to understanding the topological maintenance of human mitochondrial ...
Katja E Menger +13 more
openaire +3 more sources
Methanosarcina acetivorans C2A topoisomerase IIIα, an archaeal enzyme with promiscuity in divalent cation dependence. [PDF]
PLoS ONE, 2011 Topoisomerases play a fundamental role in genome stability, DNA replication and repair. As a result, topoisomerases have served as therapeutic targets of interest in Eukarya and Bacteria, two of the three domains of life.
Raymond Morales +3 more
doaj +1 more source
Flavonoids in Helichrysum pamphylicum Inhibit Mammalian Type I DNA Topoisomerase [PDF]
Zeitschrift für Naturforschung C, 2008 DNA topoisomerases are important targets for cancer chemotherapy. We investigated the effects of a methanolic extract of Helichrysum pamphylicum on mammalian DNA topoisomerase I via in vitro plasmid supercoil relaxation assays. The extracts manifested a considerable inhibition of the enzyme’s activity in a dose-dependent manner.
Topcu, Zeki +3 more
openaire +3 more sources
Eukaryotic DNA topoisomerases: two forms of type I DNA topoisomerases from HeLa cell nuclei. [PDF]
Proceedings of the National Academy of Sciences, 1981 Two type I DNA topoisomerases have been purified to homogeneity from the nuclei of HeLa cells. One topoisomerase has a peptide molecular weight of 100,000 and the other, a molecular weight of 67,000. Several lines of evidence indicate that these two topoisomerases are closely related, (a) Both exhibit similar enzymatic activities on DNA.
L F, Liu, K G, Miller
openaire +2 more sources
RNA topoisomerase is prevalent in all domains of life and associates with polyribosomes in animals [PDF]
, 2016 DNA Topoisomerases are essential to resolve topological problems during DNA metabolism in all species. However, the prevalence and function of RNA topoisomerases remain uncertain.
Ahmad, Muzammil +20 more
core +3 more sources
Purification and characterization of type I DNA topoisomerase fromLentinus edodes [PDF]
FEMS Microbiology Letters, 1986 Abstract Type I DNA topoisomerase was purified from the lower eukaryote Lentinus edodes . Like the topoisomerase I from other eukaryotic cells, the L. edodes enzyme removed both positive and negative superhelical turns. The M r of the enzyme was determined to be 71,500 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).
H. Kono, N. Habuka, K. Shishido
openaire +2 more sources
Pif1-Family helicases support fork convergence during DNA replication termination in eukaryotes [PDF]
, 2019 The convergence of two DNA replication forks creates unique problems during DNA replication termination. In E. coli and SV40, the release of torsional strain by type II topoisomerases is critical for converging replisomes to complete DNA synthesis, but ...
Baxter, Jonathan +4 more
core +6 more sources