Hydroxymethyluracil DNA glycosylase in mammalian cells

Journal Article · Sun Jul 01 04:00:00 EDT 1984 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.81.13.4003· OSTI ID:5766088

Hollstein, M C; Brooks, P; Linn, S; Ames, B N

An activity has been purified 350-fold from extracts of mouse plasmacytoma cells that forms 5-hydroxymethyluracil (..cap alpha..-hydroxythymine) and apyrimidinic sites with phage SPO1 DNA, which contains this base in place of thymine. This DNA glycosylase presumably functions to eliminate hydroxymethyluracil, a major thymine-derived DNA lesion produced by ionizing radiation and oxidative damage. The enzyme has no cofactor requirement and is active in EDTA. Neither intermediate formation nor hydrolysis of hydroxymethyldeoxyuridine or hydroxymethyldeoxyuridine monophosphate was detected. The enzyme does not cleave apyrimidinic sites in DNA. It does release uracil from the uracil-containing DNA of phage PBS2, but this acitivity is less than 2% of the predominant uracil DNA glycosytase activity of the cell, which is separated by phosphocellulose chromatography. The major uracil DNA glycosylase does not release hydroxymethyluracil from SPO1 DNA. The hydroxymethyluracil glycosylase is also separated upon phosphocelluose chromatography from a thymine glycol DNA glycosylase activity that is accompanied by an apyrimidinic endonuclease activity. 33 references, 2 figures, 2 tables.

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 5766088
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 81:13; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
ANIMALS
AZINES
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CARBOXYLIC ACIDS
CELL CULTURES
CHELATING AGENTS
DNA
DNA REPAIR
EDTA
ENZYME ACTIVITY
ENZYMES
GLYCOSYL HYDROLASES
HETEROCYCLIC COMPOUNDS
HYDROLASES
HYDROXY COMPOUNDS
MAMMALS
MICE
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PURIFICATION
PYRIMIDINES
RECOVERY
REPAIR
RIBOSIDES
RODENTS
THYMINE
URACILS
URIDINE
VERTEBRATES