REVIEW: Pathways of Accumulation and Repair of Deoxyuridine Residues in DNA of Higher and Lower Organisms

N. L. Vasilenko and G. A. Nevinsky^*

Novosibirsk Institute of Bioorganic Chemistry, Siberian Division of the Russian Academy of Sciences, ul. Lavrentieva 8, Novosibirsk, 630090 Russia; fax: (3832) 33-3677; E-mail: Nevinsky@niboch.nsc.ru

^* To whom correspondence should be addressed.

Received January 11, 2002; Revision received August 5, 2002

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Uracil DNA glycosylase hydrolyzes the N-glycosidic bond between sugar phosphate backbone and uracil residue appearing as the result of spontaneous deamination of cytosine or during wrong incorporation of dU residues during DNA synthesis. Uracil DNA glycosylases are very conservative enzymes. They have been recognized in all pro- and eukaryotic organisms and also in pox and herpes viruses. This review highlights the pathways of accumulation of uracil and its derivatives in DNA, the main physicochemical and biochemical properties of uracil DNA glycosylase, and regulation of its functioning. Special attention is paid to detailed mechanisms of recognition and removing of damaged (or wrong) base by uracil DNA glycosylase. These mechanisms have been validated by the methods of X-ray analysis and kinetic and thermodynamic approaches.

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KEY WORDS: accumulation of deoxyuridine in DNA, pathways of repair, uracil DNA glycosylase, structure, mechanism of action

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