title: Cloning of a Streptococcus sobrinus oligo-isomaltosaccharide synthase gene and characterization of its product.
abstract: A Streptococcus sobrinus gene coding for a glucosyltransferase (GTF)-S was cloned into Escherichia coli, using the bacteriophage lambda L47.1 and the plasmid vector pACYC184. The MD124 clone obtained expressed a 155 kDa GTF-S which did not react with any antisera against GTF-S1, -S2 and -I enzymes. The recombinant enzyme (designated rGTF-S3) was homogeneously purified from the MD124 cell-extract and characterized. The purified rGTF-S3 synthesized primer-independently alpha-1,6-linked linear oligosaccharides from sucrose. The dependence upon the sucrose concentration was diphasic, and the respective Km values were 1.3 and 25 mM. The properties except the Km values were similar to those of oligo-isomaltosaccharide synthase from S. sobrinus AHT.
authors.affiliation: Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hayakawa
authors.forename: K
authors.initials: K
authors.lastname: Fukushima
authors.forename: Y
authors.initials: Y
authors.lastname: Abiko
authors.forename: T
authors.initials: T
authors.lastname: Ikeda
authors.forename: H
authors.initials: H
authors.lastname: Takiguchi
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D005964:Glucosyltransferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005779:Immunodiffusion; D007700:Kinetics; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D016986:Streptococcus sobrinus / Q000201:enzymology* / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D005964:Glucosyltransferases