Escherichia coli DNA photolyase reverses cyclobutane pyrimidine dimers but not pyrimidine-pyrimidone (6-4) photoproducts.
نویسندگان
چکیده
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 uniformly labeled DNA. E. coli DNA photolyase removed cyclobutane dimers but had no activity on pyrimidine-pyrimidone (6-4) photoproducts. Photoreactivation can therefore be used to separate the biological effects of these two UV light-induced molecular lesions.
منابع مشابه
Kinetics of pyrimidine(6-4)pyrimidone photoproduct repair in Escherichia coli.
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عنوان ژورنال:
- The Journal of biological chemistry
دوره 260 21 شماره
صفحات -
تاریخ انتشار 1985