Identification of Repair Enzymes for 5-Formyluracil in DNA
Identification of Repair Enzymes for 5-Formyluracil in DNA
复制标题
DNA 中 5-甲酰尿嘧啶修复酶的鉴定
DOI：
--
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发表时间：
2000
影响因子：
4.8
通讯作者：
S. Yonei
中科院分区：
文献类型：
--
作者：
Qiu;I. Miyabe;Y. Matsumoto;K. Kino;H. Sugiyama;S. Yonei
5-Formyluracil (5-foU) is a potentially mutagenic lesion of thymine produced in DNA by ionizing radiation and various chemical oxidants. Although 5-foU has been reported to be removed from DNA by Escherichia coli AlkA protein in vitro, its repair mechanisms are not fully understood. In this study, we used the borohydride trapping assay to detect and characterize repair activities for 5-foU in E. coli extracts with site-specifically designed oligonucleotides containing a 5-foU at defined sites. The trapping assay revealed that there are three kinds of proteins that form covalent complexes with the 5-foU-containing oligonucleotides. Extracts from strains defective in thenth, nei, or mutM gene lacked one of the proteins. All of the trapped complexes were completely lost in extracts from the nth nei mutM triple mutant. The introduction of a plasmid carrying the nth,nei, or mutM gene into the E. colitriple mutant restored the formation of the corresponding protein-DNA complex. Purified Nth, Nei, and MutM proteins were trapped by the 5-foU-containing oligonucleotide to form the complex in the presence of NaBH4. Furthermore, the purified Nth, Nei, and MutM proteins efficiently cleaved the oligonucleotide at the 5-foU site. In addition, 5-foU was site-specifically incorporated into plasmid pSVK3, and the resulting plasmid was replicated in E. coli. The mutation frequency of the plasmid was significantly increased in theE. coli nth nei mutM alkA mutant, compared with the wild-type and alkA strains. From these results it is concluded that the Nth, Nei, and MutM proteins are involved in the repair pathways for 5-foU that serve to avoid mutations in E. coli.
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影响因子：
3.8
作者：
Rezaee M;Alizadeh E;Hunting D;Sanche L
通讯作者：
Sanche L
DOI：
10.1074/jbc.m004052200
发表时间：
2000-09
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
T. Hazra;T. Izumi;Radhika Venkataraman;Y. Kow;M. Dizdaroglu;S. Mitra
通讯作者：
T. Hazra;T. Izumi;Radhika Venkataraman;Y. Kow;M. Dizdaroglu;S. Mitra
金属对核苷氢过氧化物（DNA 中电离辐射的产物）的影响。
影响因子：
7.4
作者：
Tofigh,S;Frenkel,K
通讯作者：
Frenkel,K
影响因子：
2.9
作者：
MELAMEDE, RJ;HATAHET, Z;WALLACE, SS
通讯作者：
WALLACE, SS
影响因子：
14.9
作者：
IDE, H;KOW, YW;WALLACE, SS
通讯作者：
WALLACE, SS