Repair of O-alkylpyrimidines in mammalian cells: a present consensus.

AUTOR(ES)

Brent, T P

RESUMO

Enzymatic repair of the O-alkylpyrimidines (O2- and O4-alkylthymine, O2-alkylcytosine) and alkyl phosphotriesters has been studied in Escherichia coli, and the two proteins involved, a glycosylase (DNA-3-methyladenine glycosylase) and a methyltransferase (DNA-O6-methylguanine:protein-L-cysteine S-methyltransferase, EC 2.1.1.63), have been well characterized. In mammals or mammalian cells treated with carcinogenic alkylating agents, loss of these derivatives has been demonstrated repeatedly. Nevertheless, mammalian repair proteins that are analogous to those from E. coli do not detectably act on these alkyl derivatives. A variety of techniques has been used by many investigators in the United States and Europe, who conclude here that the mode of O-alkylpyrimidine and alkyl phosphotriester repair in mammalian cells differs from that in E. coli. New approaches and methods are needed to characterize these processes at the biochemical and molecular level.

Documentos Relacionados

• Multiple sequence alignment by consensus.
• Chromosomal Aberrations and Mortality of X-Irradiated Mammalian Cells: Emphasis on Repair
• Development of clinical guidelines in a health district: an attempt to find consensus.
• Analysis and suppression of DNA polymerase pauses associated with a trinucleotide consensus.
• A yeast DNA repair gene partially complements defective excision repair in mammalian cells.