title: Purification and properties of a novel enzyme, trehalose synthase, from Pimelobacter sp. R48.
abstract: A novel enzyme, trehalose synthase, was purified from a cell-free extract of Pimelobacter sp. R48 to an electrophoretically homogeneous state by successive chromatographies on DEAE-Toyopearl 650, Butyl-Toyopearl 650, and Mono Q HR5/5 columns. The molecular weight of the enzyme was estimated to be 62,000 by SDS-polyacrylamide gel electrophoresis, and the enzyme had a pI of 4.6 by gel isoelectrofocusing. The enzyme catalyzed the conversion of maltose into trehalose by intramolecular transglucosylation. The enzyme also converted into maltose but was inactive on other saccharides. The N-terminal amino acid of the enzyme was serine. The optimum pH and temperature were pH7.5 and 20 degrees C, respectively. The enzyme was stable in the range of pH 6.0-9.0 and up to 30 degrees C for 60 min. The rate of conversion of maltose into trehalose was independent of the maltose concentration. The maximum yield of trehalose from maltose were 81.8%, 80.9%, and 76.7% at 5, 15, and 25 degrees C, respectively. The activity was inhibited by Cu2+, Hg2+, Ni2+, Zn2+, and Tris.
authors.affiliation: Hayashibara Biochemical Laboratories, Inc., Okayama, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nishimoto
authors.forename: M
authors.initials: M
authors.lastname: Nakano
authors.forename: T
authors.initials: T
authors.lastname: Nakada
authors.forename: H
authors.initials: H
authors.lastname: Chaen
authors.forename: S
authors.initials: S
authors.lastname: Fukuda
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
authors.forename: M
authors.initials: M
authors.lastname: Kurimoto
authors.forename: Y
authors.initials: Y
authors.lastname: Tsujisaka
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D005964:Glucosyltransferases / Q000737:chemistry / Q000302:isolation & purification*; D006031:Glycosylation; D006093:Gram-Positive Asporogenous Rods / Q000235:genetics*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D000596:Amino Acids; D005964:Glucosyltransferases; C099692:trehalose synthase