Ap Endonuclease
Mostrando 1-12 de 153 artigos, teses e dissertações.
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1. Functional complementation of Leishmania (Leishmania) amazonensis AP endonuclease gene (lamap) in Escherichia coli mutant strains challenged with DNA damage agents
During its life cycle Leishmania spp. face several stress conditions that can cause DNA damages. Base Excision Repair plays an important role in DNA maintenance and it is one of the most conserved mechanisms in all living organisms. DNA repair in trypanosomatids has been reported only for Old World Leishmania species. Here the AP endonuclease from Leishmania
Mem. Inst. Oswaldo Cruz. Publicado em: 2016-05
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2. Caracterização de dois cDNAs homológos e uma AP endonuclease em cana-de-açúcar
The genome of all organisms is subject to injuries that can be caused by endogenous and environmental factors. If these lesions are not corrected, it can be fixed generating a mutation which can be lethal to the organisms. In order to prevent this, there are different DNA repair mechanisms. These mechanisms are well known in bacteria, yeast, human, but not i
Publicado em: 2009
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3. The mechanisms of action of E. coli endonuclease III and T4 UV endonuclease (endonuclease V) at AP sites.
Treatment of DNA containing AP sites with either T4 UV endonuclease or with E. coli endonuclease III followed by a human class II AP endonuclease releases a putative beta-elimination product. This result suggests that both the T4 endonuclease and E. coli endonuclease III class I AP endonucleases catalyze phosphodiester bond cleavage via a lyase- rather than
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4. Selective inhibition by harmane of the apurinic apyrimidinic endonuclease activity of phage T4-induced UV endonuclease.
1-Methyl-9H-pyrido-[3,4-b]indole (harmane) inhibits the apurinic/apyrimidinic (AP) endonuclease activity of the UV endonuclease induced by phage T4, whereas it stimulates the pyrimidine dimer-DNA glycosylase activity of that enzyme. E. coli endonuclease IV, E. coli endonuclease VI (the AP endonuclease activity associated with E. coli exonuclease III), and E.
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5. Purification and amino-terminal amino acid sequence of an apurinic/apyrimidinic endonuclease from calf thymus.
An apurinic/apyrimidinic (AP) endonuclease (E.C.3.1.25.2) has been purified 1100 fold to apparent homogeneity from calf thymus by a series of ion exchange, gel filtration and hydrophobic interaction chromatographies. The purified AP endonuclease is a monomeric protein with an apparent molecular weight on SDS-PAGE of 37,000. On gel filtration the protein beha
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6. Recognition of oxidized abasic sites by repair endonucleases.
The recognition of 'regular' and 'oxidized' sites of base loss (AP sites) in DNA by various AP endonucleases was compared. Model substrates with regular AP sites (resulting from mere hydrolysis of the glycosylic bond) were produced by damaging bacteriophage PM2 DNA by exposure to low pH; those with AP sites oxidized at the C-4'- and C-1'-position of the suga
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7. Analysis of class II (hydrolytic) and class I (beta-lyase) apurinic/apyrimidinic endonucleases with a synthetic DNA substrate.
We have developed simple and sensitive assays that distinguish the main classes of apurinic/apyrimidinic (AP) endonucleases: Class I enzymes that cleave on the 3' side of AP sites by beta-elimination, and Class II enzymes that cleave by hydrolysis on the 5' side. The distinction of the two types depends on the use of a synthetic DNA polymer that contains AP
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8. Repair of apurinic/apyrimidinic sites by UV damage endonuclease; a repair protein for UV and oxidative damage.
UV damage endonuclease (UVDE) initiates a novel form of excision repair by introducing a nick imme-diately 5" to UV-induced cyclobutane pyrimidine dimers or 6-4 photoproducts. Here, we report that apurinic/apyrimidinic (AP) sites are also nicked by Neurospora crassa and Schizosaccharomyces pombe UVDE. UVDE introduces a nick immediately 5" to the AP site leav
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9. Isolation of cDNA clones encoding a human apurinic/apyrimidinic endonuclease that corrects DNA repair and mutagenesis defects in E. coli xth (exonuclease III) mutants.
Apurinic/apyrimidinic (AP) sites in cellular DNA are considered to be both cytotoxic and mutagenic, and can arise spontaneously or following exposure to DNA damaging agents. We have isolated cDNA clones which encode an endonuclease, designated HAP1 (human AP endonuclease 1), that catalyses the initial step in AP site repair in human cells. The predicted HAP1
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10. Escherichia coli MutY protein has both N-glycosylase and apurinic/apyrimidinic endonuclease activities on A.C and A.G mispairs.
In Escherichia coli the mutY (or micA)-dependent DNA mismatch repair pathway can convert A degrees G and A degrees C mismatches to C.G and G.C base pairs, respectively, through a short repair-tract mechanism. The MutY protein has been purified to near homogeneity from an E. coli overproducer strain. Purified MutY has been shown to contain both N-glycosylase
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11. Interaction of human apurinic endonuclease and DNA polymerase β in the base excision repair pathway
Mutagenic abasic (AP) sites are generated directly by DNA-damaging agents or by DNA glycosylases acting in base excision repair. AP sites are corrected via incision by AP endonucleases, removal of deoxyribose 5-phosphate, repair synthesis, and ligation. Mammalian DNA polymerase β (Polβ) carries out most base excision repair synthesis and also can excise de
The National Academy of Sciences of the USA.
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12. Mechanism of incision by an apurinic/apyrimidinic endonuclease present in human placenta.
An apparently homogeneous enzyme preparation, containing an apurinic/apyrimidinic (AP) endonuclease from human placenta, was by DNA sequencing analysis found to act as a class I AP-endonuclease, i.e. produce a 3'-deoxyribose and 5'-phosphomonoester nucleotide termini.