title: Evidence for phosphate adducts in DNA from mice treated with 4-(N-Methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK).
abstract: The weakly alkylating capacity of phosphotriesters (PTE) has been used for the determination of adducts to phosphate groups in DNA by specific transfer to the strongly nucleophilic compound cob(I)alamin [Cbl(I)]. When enzymatically degraded liver DNA from mice treated with 1-(N-methyl-N-nitrosamino)-4-(3-[3H]pyridyl)-4-oxobutane ([3H]NNK) was added to Cbl(I), a 4-(3-[3H]pyridyl)-4-hydroxy-1-butyl-cobalamin ([3H]PHB-Cbl) complex was formed and determined by HPLC and liquid scintillation counting. The PHB-Cbl formed was compared with a synthetic standard verified by LC/MS and 1H NMR and corresponds to phosphate adducts formed from the pyridyloxobutylating species from NNK and from the pyridylhydroxybutylating species from NNAL, NNK being to a large extent converted to NNAL in vivo. It was concluded that about 22% of the total level of pyridyl (oxo or hydroxy) butyl adducts to DNA was bound to phosphate groups.
authors.affiliation: Department of Genetic and Cellular Toxicology, Stockholm University, Sweden.
authors.forename: Johanna
authors.initials: J
authors.lastname: Haglund
authors.forename: Alistair P
authors.initials: AP
authors.lastname: Henderson
authors.forename: Bernard T
authors.initials: BT
authors.lastname: Golding
authors.forename: Margareta
authors.initials: M
authors.lastname: Törnqvist
mesh_terms: D000478:Alkylation; D000818:Animals; D001711:Biotransformation; D002273:Carcinogens / Q000378:metabolism* / Q000633:toxicity*; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000187:drug effects / Q000378:metabolism; D018736:DNA Adducts / Q000032:analysis / Q000096:biosynthesis*; D006900:Hydroxylation; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D051379:Mice; D009602:Nitrosamines / Q000378:metabolism* / Q000633:toxicity*; D010710:Phosphates / Q000378:metabolism*; D010727:Phosphoric Diester Hydrolases / Q000737:chemistry; D010880:Piperidines / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D014805:Vitamin B 12 / Q000031:analogs & derivatives / Q000737:chemistry
chemical_list: D002273:Carcinogens; D018736:DNA Adducts; D009602:Nitrosamines; D010710:Phosphates; D010880:Piperidines; C016583:4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone; D004247:DNA; D010727:Phosphoric Diester Hydrolases; D014805:Vitamin B 12; C084823:pipradrol