Dna Topoisomerases Type Ii
Mostrando 1-12 de 74 artigos, teses e dissertações.
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1. Cinética celular na endometriose profunda infiltrativa de reto-sigmoide: estudo anátomo-clínico / Cell kinetics in deep infiltrating endometriosis of rectosigmoid: an anatomoclinical study
INTRODUÇÃO: A endometriose, uma doença benigna, tem características invasivas com potencial proliferativo. O desenvolvimento das lesões pode ocorrer em decorrência de crescimento celular glandular e/ou estromal ou de alterações na cinética celular. Cinética celular refere-se ao equilíbrio entre a morte celular, ou apoptose, e a proliferação celu
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 13/09/2011
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2. Caracterização genômica da bactéria endossimbiótica do tripanosomatídeo Crithidia deanei e de suas DNA topoisomerases / Genomics characterization of the endosymbiont bacterium of the tripanosomatídeo Crithidia deanei and of its DNA topoisomerases
The present work is focused in the endosymbiont type II topoisomerases, due to their essential roles not only in the replication and transcription processes but also at the recombination and chromosome segregation processes. There are two Type II topoisomerases in bacteria: DNA gyrase and DNA Topoisomerase IV. DNA gyrase is the only topoisomerase capable of
Publicado em: 2006
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3. SÃntese e avaliaÃÃo da atividade biolÃgica de novos derivados acridino-tiazolidÃnicos e acridino-imidazolidÃnicos / SÃntese e avaliaÃÃo da atividade biolÃgica de novos derivados acridino-tiazolidÃnicos e acridino-imidazolidÃnicos
The acridines compounds present an ample variety of biological effect that can be attributed, in its great majority, its ability to bind the DNA, intercalating themselves it between the pairs of basis and blocking the action of topoisomerases I and II. In literature, compounds possessing the acridine ring are distinguished for presenting activities antimalar
Publicado em: 2003
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4. DNA topoisomerase inhibitors: biflavonoids from Ouratea species
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. These biflavonoids and the acetyl derivative of II (IIa) are inhibitors of human DNA topoisomerases I at 200 µM, as demonstrated
Brazilian Journal of Medical and Biological Research. Publicado em: 2002-07
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5. Sensitivity of human type II topoisomerases to DNA damage: stimulation of enzyme-mediated DNA cleavage by abasic, oxidized and alkylated lesions
Type II topoisomerases are essential enzymes that are also the primary cellular targets for a number of important anticancer drugs. These drugs act by increasing levels of topoisomerase II-mediated DNA cleavage. Recent studies indicate that endogenous forms of DNA damage, such as abasic sites and base mismatches, also stimulate the DNA scission activity of t
Oxford University Press.
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6. Antibacterial Activities and Inhibitory Effects of Sitafloxacin (DU-6859a) and Its Optical Isomers against Type II Topoisomerases
The in vitro inhibitory effects of sitafloxacin (DU-6859a) and its three stereoisomers on bacterial DNA gyrase from Escherichia coli, topoisomerase IV from Staphylococcus aureus, and topoisomerase II from human placenta were compared. No correlation was observed between the inhibitory activities of quinolones against bacterial type II topoisomerases and thos
American Society for Microbiology.
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7. Mechanism of topology simplification by type II DNA topoisomerases
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, providin
The National Academy of Sciences.
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8. Novel topologically knotted DNA from bacteriophage P4 capsids: studies with DNA topoisomerases.
DNA molecules isolated from bacteriophage P4 are mostly linear with cohesive ends capable of forming circular and concatemeric structures. In contrast, almost all DNA molecules isolated form P4 tailless capsids (heads) are monomeric DNA circles with their cohesive ends hydrogen-bonded. Different form simple DNA circles, such P4 head DNA circles contain topol
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9. Conversion of DNA gyrase into a conventional type II topoisomerase
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. Novobiocin, a competitive inhibitor of ATP bin
The National Academy of Sciences of the USA.
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10. Inhibitory Activities of Gatifloxacin (AM-1155), a Newly Developed Fluoroquinolone, against Bacterial and Mammalian Type II Topoisomerases
We determined the inhibitory activities of gatifloxacin against Staphylococcus aureus topoisomerase IV, Escherichia coli DNA gyrase, and HeLa cell topoisomerase II and compared them with those of several quinolones. The inhibitory activities of quinolones against these type II topoisomerases significantly correlated with their antibacterial activities or cyt
American Society for Microbiology.
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11. Structural similarities between topoisomerases that cleave one or both DNA strands
Type IA and type II DNA topoisomerases are distinguished by their ability to cleave one or two strands, respectively, of a DNA duplex. Both types have been proposed to use an “enzyme-bridging” mechanism, in which a break is formed in a DNA strand and a gap is opened between the broken pieces to allow passage of a second DNA strand or duplex segment. Alth
The National Academy of Sciences.
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12. The mechanism of type IA topoisomerases
The topology of cellular DNA is carefully controlled by enzymes called topoisomerases. By using single-molecule techniques, we monitored the activity of two type IA topoisomerases in real time under conditions in which single relaxation events were detected. The strict one-at-a-time removal of supercoils we observed establishes that these enzymes use an enzy
National Academy of Sciences.