title: Conformation and physical properties of cycloisomaltooligosaccharides in aqueous solution.
abstract: We studied the conformation and physical properties of cyclic and linear isomaltooligosaccharides in aqueous solution by intrinsic viscosity measurement, small angle X-ray scattering (SAXS) and molecular modeling. We used four cycloisomaltooligosaccharide samples (CIs) with degree of polymerization (DP) 7-10 (CI-7-CI-10) and five linear isomaltooligosaccharide samples (LIs) with DP 7-11 (LI-7-LI-11). The values of α in the Mark-Houwink-Sakurada equation [η]=KM(w)(α) for the CI and LI were determined to be 0.50 and 0.78, respectively. The radii of gyration (R(G)) of CI-7, CI-8, CI-9 and CI-10 determined from SAXS data were 6.7, 6.9, 7.5 and 8.3Å, respectively. The scattering profile of CI-9 compared with those obtained for molecular models indicated that CI molecular chains are less flexible than those for LIs and adopt a rather compact circular conformation.
authors.affiliation: Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Japan.
authors.forename: Shiho
authors.initials: S
authors.lastname: Suzuki
authors.forename: Takashi
authors.initials: T
authors.lastname: Yukiyama
authors.forename: Arata
authors.initials: A
authors.lastname: Ishikawa
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yuguchi
authors.forename: Kazumi
authors.initials: K
authors.lastname: Funane
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kitamura
mesh_terms: D003500:Cyclization; D003911:Dextrans / Q000737:chemistry; D005964:Glucosyltransferases / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D053838:Scattering, Small Angle; D014783:Viscosity; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D003911:Dextrans; D009844:Oligosaccharides; C021705:maltooligosaccharides; D014867:Water; D005964:Glucosyltransferases; C087517:cycloisomaltooligosaccharide glucanotransferase
keywords: Cycloisomaltooligosaccharide; Intrinsic viscosities; Molecular dynamic simulation; Small angle X-ray scattering