title: Single-molecule force spectroscopy for studying kinetics of enzymatic dextran elongations.
abstract: Catalytic elongation of dextran by a single molecule of dextransucrase (DSase) was directly monitored by observing the movements of the positions of a rupture peak, which represented the adhesive force between an isomaltoheptaose (dextran 7-mer)-immobilized probe and a DSase-immobilized mica surface. This was initiated with the addition of sucrose monomers. From the histograms of the rupture peaks after elongation reactions on each individual enzyme and the continuous peak shift of certain single enzymes, the catalytic elongation rate constant (k(cat)) was ascertained to be 1.2-2.7 s(-1).
authors: Department of Biomolecular Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan. tmori@bio.titech.ac.jp
authors: Toshiaki
authors: T
authors: Mori
authors: Megumi
authors: M
authors: Asakura
authors: Yoshio
authors: Y
authors: Okahata
mesh_terms: D003911:Dextrans / Q000378:metabolism*; D004800:Enzymes, Immobilized / Q000378:metabolism; D005964:Glucosyltransferases / Q000378:metabolism*; D007700:Kinetics; D013057:Spectrum Analysis / Q000379:methods*; D013395:Sucrose / Q000378:metabolism
chemical_list: D003911:Dextrans; D004800:Enzymes, Immobilized; D013395:Sucrose; D005964:Glucosyltransferases; C020025:dextransucrase