Kinetics of pyrimidine(6-4)pyrimidone photoproduct repair in Escherichia coli.
نویسندگان
چکیده
We compared the removal of pyrimidine(6-4)pyrimidone photoproducts [(6-4) photoproducts] and cyclobutane pyrimidine dimers (CPDs) from the genome of repair-proficient Escherichia coli, using monoclonal antibodies specific for each type of lesion. We found that (6-4) photoproducts were removed at a higher rate than CPDs in the first 30 min following a moderate UV dose (40 J/m2). The difference in rates was less than that typically reported for cultured mammalian cells, in which the removal of (6-4) photoproducts is far more rapid than that of CPDs.
منابع مشابه
Escherichia coli DNA photolyase reverses cyclobutane pyrimidine dimers but not pyrimidine-pyrimidone (6-4) photoproducts.
The effect of purified Escherichia coli DNA photolyase on the UV light-induced pyrimidine-pyrimidone (6-4) photoproduct and cyclobutane pyrimidine dimer was investigated in vitro using enzyme purified from cells carrying the cloned phr gene (map position, 15.7 min). Photoproducts were examined both as site-specific lesions in end-labeled DNA and as chromatographically identified products in uni...
متن کاملThe C-C (6-4) UV photoproduct is mutagenic in Escherichia coli.
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Ultraviolet light induces cyclobutane pyrimidine dimers (CPD) and pyrimidine(6-4)pyrimidone photoproducts, which interfere with DNA replication and transcription. Nucleotide excision repair (NER) removes these photoproducts, but whether NER functions at telomeres is unresolved. Here we use immunospot blotting to examine the efficiency of photoproduct formation and removal at telomeres purified ...
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We synthesized a dinucleoside monophosphate of the (15)N-labeled (6-4) photoproduct, which is one of the major UV-induced lesions in DNA, to investigate the (6-4) photolyase repair mechanism, and characterized its protonation state by measuring (15)N NMR spectra as a function of pH. We expected that chemical-shift changes of the pyrimidone (15)N3, due to protonation, would be observed at pH 3, ...
متن کاملQuantum-chemical investigation of the photoproduct of the reaction of two 1-methylthymine molecules: the pyrimidine(6-4)pyrimidone adduct
One of the products of the photochemical reaction induced by UV irradiation of the two 1-methylthymine molecules is pyrimidine(6-4)pyrimidone. Due to the low yield of this product, it is difficult to examine its geometry and vibrational spectrum. In this study, quantum chemical methods were used to characterize the structure of pyrimidine(6-4)pyrimidone. Its three conformers were optimized and ...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 178 5 شماره
صفحات -
تاریخ انتشار 1996