title: Characterization of a Thermostable 8-Oxoguanine DNA Glycosylase Specific for GO/N Mismatches from the Thermoacidophilic ArchaeonThermoplasma volcanium.
abstract: The oxidation of guanine (G) to 7,8-dihydro-8-oxoguanine (GO) forms one of the major DNA lesions generated by reactive oxygen species (ROS). The GO can be corrected by GO DNA glycosylases (Ogg), enzymes involved in base excision repair (BER). Unrepaired GO induces mismatched base pairing with adenine (A); as a result, the mismatch causes a point mutation, from G paired with cytosine (C) to thymine (T) paired with adenine (A), during DNA replication. Here, we report the characterization of a putative Ogg from the thermoacidophilic archaeonThermoplasma volcanium. The 204-amino acid sequence of the putative Ogg (TVG_RS00315) shares significant sequence homology with the DNA glycosylases ofMethanocaldococcus jannaschii(MjaOgg) andSulfolobus solfataricus(SsoOgg). The six histidine-tagged recombinant TVG_RS00315 protein gene was expressed inEscherichia coliand purified. The Ogg protein is thermostable, with optimal activity near a pH of 7.5 and a temperature of 60°C. The enzyme displays DNA glycosylase, and apurinic/apyrimidinic (AP) lyase activities on GO/N (where N is A, T, G, or C) mismatch; yet it cannot eliminate U from U/G or T from T/G, as mismatch glycosylase (MIG) can. These results indicate that TvoOgg-encodingTVG_RS00315is a member of the Ogg2 family ofT. volcanium.
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Miki
authors: M
authors: Fujii
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Chieri
authors: C
authors: Hata
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Munetada
authors: M
authors: Ukita
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Chie
authors: C
authors: Fukushima
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Chihiro
authors: C
authors: Matsuura
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Yoshie
authors: Y
authors: Kawashima-Ohya
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Koji
authors: K
authors: Tomobe
authors: Department of Molecular Biology, Faculty of Pharmaceutical Science, Yokohama University of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066, Japan.
authors: Tsuyoshi
authors: 0000-0001-5055-1562
authors: T
authors: Kawashima
mesh_terms: D004247:DNA / Q000378:metabolism*; D045647:DNA Glycosylases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006147:Guanine / Q000031:analogs & derivatives* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D013822:Thermoplasma / Q000201:enzymology* / Q000235:genetics
chemical_list: C453560:7,8-dihydro-8-oxoguanine; D011994:Recombinant Proteins; D006147:Guanine; D004247:DNA; D045647:DNA Glycosylases