title: Four different types of glucans synthesised by glucosyltransferases from Streptococcus sobrinus.
abstract: Four different kinds of glucosyltransferases (GTFs) were purified from the cariogenic bacterium Streptococcus sobrinus AHT. One of them (GTFP3) produced water-insoluble glucan with the alpha-1,3 linkage, exclusively. The others (GTFP1, P2 and P4) produced water-soluble glucans. GTFP2 produced oligosaccharides with linear 1,6-alpha-D-glucan structure. Since GTFP1 and P4 produce similar molecular weight glucans, the structural differences between these glucans remain unclear. To clarify the difference between GTFP1 and P4 products, the glucan structures were investigated by methylation analysis with gas liquid chromatography and gas liquid chromatography-mass spectrometry. The glucan synthesised by GTFP1 was 1,6-alpha-D-glucan with a high percentage (25.9 mol%) of 1,3-alpha-D-linked units. The other glucan synthesised by GTFP4 contained 1,6-alpha-D-glucan with 1,3,6-alpha-D-glucose (18.5 mol%).
authors.affiliation: Department of Preventive Dentistry, Iwate Medical University, School of Dentistry, Morioka, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Hanada
authors.forename: T
authors.initials: T
authors.lastname: Katayama
authors.forename: A
authors.initials: A
authors.lastname: Kunimori
authors.forename: Y
authors.initials: Y
authors.lastname: Yamashita
authors.forename: T
authors.initials: T
authors.lastname: Takehara
mesh_terms: D005936:Glucans / Q000096:biosynthesis / Q000737:chemistry*; D005964:Glucosyltransferases / Q000378:metabolism*; D016986:Streptococcus sobrinus / Q000201:enzymology / Q000378:metabolism*
chemical_list: D005936:Glucans; D005964:Glucosyltransferases