title: Restriction endonuclease Aor13HI from Acidiphilium organovorum 13H, a new isoschizomer of BspMII: purification and characterization.
abstract: A restriction endonuclease, Aor13HI, an isoschizomer of BspMII, was purified to homogeneity from cell extracts of Acidiphilium organovorum strain 13H. The enzyme has a molecular mass of 60,000 daltons and consists of two subunits identical in molecular mass of 30,000 daltons. Aor13HI endonuclease, like BspMII, recognizes the palindromic six-base sequence 5'-TCCGGA-3', and cleaves between the T and C to produce a four-base 5' extension. Aor13HI is not inhibited by dam-dependent methylation. The isoelectric point of the enzyme is 5.7. Aor13HI activity was maximum at pH 7.5, 100 mM KCl, 7.5-10 mM MgCl2, and 55 degrees C. The enzyme was stable up to 60 degrees C. The N-terminal amino acid sequence (30 residues) of Aor13HI did not show any similarity with the sequence of other restriction endonucleases reported.
authors.affiliation: Division of Bioresources Science, Faculty of Agriculture, Okayama University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Inagaki
authors.forename: T
authors.initials: T
authors.lastname: Hikita
authors.forename: S
authors.initials: S
authors.lastname: Yanagidani
authors.forename: Y
authors.initials: Y
authors.lastname: Nomura
authors.forename: N
authors.initials: N
authors.lastname: Kishimoto
authors.forename: T
authors.initials: T
authors.lastname: Tano
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002850:Chromatography, Gel; D002942:Circular Dichroism; D015252:Deoxyribonucleases, Type II Site-Specific / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D006091:Gram-Negative Chemolithotrophic Bacteria / Q000201:enzymology* / Q000254:growth & development; D007526:Isoelectric Point; D008745:Methylation; D008969:Molecular Sequence Data; D008970:Molecular Weight
chemical_list: D015252:Deoxyribonucleases, Type II Site-Specific; C053919:TCCGGA-specific type II deoxyribonucleases