title: A functional endonuclease Q exists in the bacterial domain: identification and characterization of endonuclease Q from Bacillus pumilus.
abstract: DNA base deamination occurs spontaneously under physiological conditions and is promoted by high temperature. Therefore, hyperthermophiles are expected to have efficient repair systems of the deaminated bases in their genomes. Endonuclease Q (EndoQ) was originally identified from the hyperthermophlic archaeon, Pyrococcus furiosus, as a hypoxanthine-specific endonuclease recently. Further biochemical analyses revealed that EndoQ also recognizes uracil, xanthine, and the AP site in DNA, and is probably involved in a specific repair process for damaged bases. Initial phylogenetic analysis showed that an EndoQ homolog is found only in the Thermococcales and some of the methanogens in Archaea, and is not present in most members of the domains Bacteria and Eukarya. A better understanding of the distribution of the EndoQ-mediated repair system is, therefore, of evolutionary interest. We showed here that an EndoQ-like polypeptide from Bacillus pumilus, belonging to the bacterial domain, is functional and has similar properties with the archaeal EndoQs.
authors.affiliation: a Graduate School of Bioresource and Bioenvironmental Sciences , Kyushu University , Fukuoka , Japan.|d Institute for Universal Biology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.|e Carl R. Woese Institute for Genomic Biology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.
authors.forename: Miyako
authors.initials: M
authors.lastname: Shiraishi
authors.affiliation: a Graduate School of Bioresource and Bioenvironmental Sciences , Kyushu University , Fukuoka , Japan.
authors.forename: Sonoko
authors.initials: S
authors.lastname: Ishino
authors.affiliation: b Department of Animal Science , University of Illinois at Urbana-Champaign , Urbana , IL , USA.|c Department of Microbiology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.|d Institute for Universal Biology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.|e Carl R. Woese Institute for Genomic Biology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.
authors.forename: Isaac
authors.initials: I
authors.lastname: Cann
authors.affiliation: a Graduate School of Bioresource and Bioenvironmental Sciences , Kyushu University , Fukuoka , Japan.|d Institute for Universal Biology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.|e Carl R. Woese Institute for Genomic Biology , University of Illinois at Urbana-Champaign , Urbana , IL , USA.
authors.forename: Yoshizumi
authors.initials: Y
authors.lastname: Ishino
mesh_terms: D000595:Amino Acid Sequence; D001105:Archaea / Q000201:enzymology / Q000235:genetics; D000069979:Bacillus pumilus / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004720:Endonucleases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010802:Phylogeny; D012689:Sequence Homology, Nucleic Acid; D013379:Substrate Specificity
chemical_list: D004720:Endonucleases
keywords: Archaea; DNA repair; base deamination; endonuclease; molecular evolution