title: Amylosucrase from Neisseria polysaccharea: novel catalytic properties.
abstract: Amylosucrase is a glucosyltransferase that synthesises an insoluble alpha-glucan from sucrose. The catalytic properties of the highly purified amylosucrase from Neisseria polysaccharea were characterised. Contrary to previously published results, it was demonstrated that in the presence of sucrose alone, several reactions are catalysed, in addition to polymer synthesis: sucrose hydrolysis, maltose and maltotriose synthesis by successive transfers of the glucosyl moiety of sucrose onto the released glucose, and finally turanose and trehalulose synthesis - these two sucrose isomers being obtained by glucosyl transfer onto fructose. The effect of initial sucrose concentration on initial activity demonstrated a non-Michaelian profile never previously described.
authors.affiliation: Centre de Bioingénierie Gilbert Durand, UMR CNRS 5504, UMR INRA 792, INSA, Complexe Scientifique de Rangueil, 31077, Toulouse, France.
authors.forename: G
authors.initials: G
authors.lastname: Potocki de Montalk
authors.forename: M
authors.initials: M
authors.lastname: Remaud-Simeon
authors.forename: R M
authors.initials: RM
authors.lastname: Willemot
authors.forename: P
authors.initials: P
authors.lastname: Sarçabal
authors.forename: V
authors.initials: V
authors.lastname: Planchot
authors.forename: P
authors.initials: P
authors.lastname: Monsan
mesh_terms: D002384:Catalysis / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004187:Disaccharides / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005632:Fructose / Q000378:metabolism / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism; D005964:Glucosyltransferases / Q000302:isolation & purification / Q000378:metabolism*; D006868:Hydrolysis / Q000187:drug effects; D007536:Isomerism; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008320:Maltose / Q000378:metabolism; D009343:Neisseria / Q000201:enzymology*; D011108:Polymers / Q000737:chemistry / Q000378:metabolism; D012995:Solubility; D013395:Sucrose / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D014312:Trisaccharides / Q000378:metabolism
chemical_list: D004187:Disaccharides; D011108:Polymers; D014312:Trisaccharides; D005632:Fructose; D013395:Sucrose; C008317:maltotriose; D008320:Maltose; C029454:turanose; D005964:Glucosyltransferases; C019700:amylosucrase; C042003:trehalulose; D005947:Glucose