title: Characterization of a RecA/RAD51 homologue from the hyperthermophilic archaeon Pyrococcus sp. KOD1.
abstract: The Pk-rec gene, encoding a RecA/RAD51 homologue from the hyperthermophilic archaeon Pyrococcussp. KOD1, was expressed in Escherichia coli. The recombinant Pk-REC was purified to homogeneity and was shown to be in a dimeric form. A striking property of the purified recombinant Pk-REC was the unusual DNase activity on both single- and double-stranded DNAs along with the ATPase activity. The reaction product of this DNase activity was mononucleotides. The optimum temperature and pH for the DNase activity were 60 degrees C and 8-8.5, respectively. In addition, the metal ion requirement for DNase activity was different from that for the ATPase activity. The protein exhibited no DNase activity in the presence of Zn2+ion, which was one of the most preferable divalent cations for ATPase activity. Another unique characteristic of the recombinant protein was that the reaction product of ATPase activity was AMP instead of ADP.Pk-REC may represent a common prototype of the RecA family proteins with high RecA-like activity.
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Rashid
authors.forename: M
authors.initials: M
authors.lastname: Morikawa
authors.forename: K
authors.initials: K
authors.lastname: Nagahisa
authors.forename: S
authors.initials: S
authors.lastname: Kanaya
authors.forename: T
authors.initials: T
authors.lastname: Imanaka
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001105:Archaea / Q000737:chemistry* / Q000201:enzymology / Q000235:genetics; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D003851:Deoxyribonucleases / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D005822:Genetic Vectors; D010802:Phylogeny; D051135:Rad51 Recombinase; D011938:Rec A Recombinases / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D051135:Rad51 Recombinase; D011938:Rec A Recombinases; D003851:Deoxyribonucleases; D000251:Adenosine Triphosphatases