Repair of O6-methylguanine adducts in human telomeric G-quadruplex DNA by O6-alkylguanine-DNA alkyltransferase
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منابع مشابه
Repair of O6-methylguanine adducts in human telomeric G-quadruplex DNA by O6-alkylguanine-DNA alkyltransferase
O(6)-alkylguanine-DNA alkyltransferase (AGT) is a single-cycle DNA repair enzyme that removes pro-mutagenic O(6)-alkylguanine adducts from DNA. Its functions with short single-stranded and duplex substrates have been characterized, but its ability to act on other DNA structures remains poorly understood. Here, we examine the functions of this enzyme on O(6)-methylguanine (6mG) adducts in the fo...
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Rates of individual steps in the removal of alkyl groups from O6-methyl (Me) and -benzyl (Bz) guanine in oligonucleotides by human O6-alkylguanine DNA alkyltransferase (AGT) were estimated using rapid reaction kinetic methods. The overall reaction yields hyperbolic plots of rate versus AGT concentration for O6-MeG but linear plots for the O6-BzG reaction, which is approximately 100-fold faster....
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Binding experiments with alkyl-transfer-active and -inactive mutants of human O(6)-alkylguanine DNA alkyltransferase (AGT) show that it forms an O(6)-methylguanine (6mG)-specific complex on duplex DNA that is distinct from non-specific assemblies previously studied. Specific complexes with duplex DNA have a 2:1 stoichiometry that is formed without accumulation of a 1:1 intermediate. This establ...
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ژورنال
عنوان ژورنال: Nucleic Acids Research
سال: 2014
ISSN: 1362-4962,0305-1048
DOI: 10.1093/nar/gku659