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
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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
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
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
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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
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Inhibitory Activities of Helichrysum . Taxa on Mammalian Type I DNA Topoisomerase [PDF]
Pharmaceutical Biology, 2006 AbstractDNA topoisomerases are essential enzymes that regulate the conformational changes in DNA topology by catalyzing the concerted breakage and rejoining of DNA strands during normal cellular growth. During the past few years, there has been considerable pharmacological interest in these enzymes because the inhibitors of DNA topoisomerases represent
Kucukoglu, O. +3 more
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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
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DNA topoisomerase inhibitors: biflavonoids from Ouratea species
Brazilian Journal of Medical and Biological Research, 2002 Topoisomerase inhibitors are agents with anticancer activity. 7"-O-Methyl-agathisflavone (I) and amentoflavone (II) are biflavonoids and were isolated from the Brazilian plants Ouratea hexasperma and O. semiserrata, respectively.
N.F. Grynberg +6 more
doaj +1 more source
Topoisomerase 3alpha and RMI1 suppress somatic crossovers and are essential for resolution of meiotic recombination intermediates in Arabidopsis thaliana. [PDF]
PLoS Genetics, 2008 Topoisomerases are enzymes with crucial functions in DNA metabolism. They are ubiquitously present in prokaryotes and eukaryotes and modify the steady-state level of DNA supercoiling.
Frank Hartung +4 more
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Overexpression of Type I Topoisomerases Sensitizes Yeast Cells to DNA Damage [PDF]
Journal of Biological Chemistry, 2001 DNA topoisomerases play essential roles in many DNA metabolic processes. It has been suggested that topoisomerases play an essential role in DNA repair. Topoisomerases can introduce DNA damage upon exposure to drugs that stabilize the covalent protein-DNA intermediate of the topoisomerase reaction. Lesions in DNA are also able to trap topoisomerase-DNA
J L, Nitiss +3 more
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