Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Removal of hydantoin products of 8-oxoguanine oxidation by the Escherichiacoli DNA repair enzyme, FPG
Autore:
Leipold, MD; Muller, JG; Burrows, CJ; David, SS;
Indirizzi:
Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA Univ Utah Salt Lake City UT USA 84112 Chem, Salt Lake City, UT 84112 USA
Titolo Testata:
BIOCHEMISTRY
fascicolo: 48, volume: 39, anno: 2000,
pagine: 14984 - 14992
SICI:
0006-2960(200012)39:48<14984:ROHPO8>2.0.ZU;2-7
Fonte:
ISI
Lingua:
ENG
Soggetto:
BASE-EXCISION-REPAIR; ELECTRON-TRANSFER; SYNTHESIS PAST; DAMAGED DNA; ZINC-FINGER; WILD-TYPE; PROTEIN; GLYCOSYLASE; DUPLEX; 7,8-DIHYDRO-8-OXOGUANINE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
72
Recensione:
Indirizzi per estratti:
Indirizzo: David, SS Univ Utah, Dept Chem, 315 South 1400 East, Salt Lake City, UT 84112 USA Univ Utah 315 South 1400 East Salt Lake City UT USA 84112 12 USA
Citazione:
M.D. Leipold et al., "Removal of hydantoin products of 8-oxoguanine oxidation by the Escherichiacoli DNA repair enzyme, FPG", BIOCHEM, 39(48), 2000, pp. 14984-14992

Abstract

An intriguing feature of 7,8-dihydro-8-oxo-2'-deoxyguanosine (OG) is that it is highly reactive toward further oxidation. Indeed, OG has been shown to be a "hot spot" for oxidative damage and susceptible to oxidation by a variety of cellular oxidants, Recent work has identified two new DNA lesions,guanidinohydantoin (Gh) and spiroiminodihydantoin (Sp), resulting from one-electron oxidation of OG, The presence of Gh and Sp lesions in DNA templates has been shown to result in misinsertion of G and A by DNA polymerases, and therefore, both are potentially mutagenic DNA lesions. The base excision repair (BER) glycosylases Fpg and MutY serve to prevent mutations associated with OG in Escherichia coli, and therefore, we have investigated the ability of these two enzymes to process DNA duplex substrates containing the further oxidized OG lesions, Gh and Sp. The Fpg protein, which removes OG and a variety of other oxidized purine base lesions, was found to remove Gh and Sp efficiently opposite all four of the natural DNA bases. The intrinsic rate of damaged base excision by Fpg was measured under single-turnover conditions and was found to be highly dependent upon the identity of the base opposite the OG, Gh, or Sp lesion; as expected, OG is removed more readily from an OG:C- than an OG:A-containing substrate. However, when adenine ispaired with Gh or Sp, the rate of removal of these damaged lesions by Fpg was significantly increased relative to the rate of removal of OG from an OG:A mismatch, The adenine glycosylase MutY, which removes misincorporated Aresidues from OG:A mismatches, is unable to remove A paired with Gh or Sp. Thus, the activity of Fpg on Gh and Sp lesions may dramatically influence their mutagenic potential. This work suggests that, in addition to OG, oxidative products resulting from further oxidation of OG should be considered when evaluating oxidative DNA damage and its associated effects on DNA mutagenesis.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 21/09/20 alle ore 06:35:11