title: The rate of spontaneous cleavage of the glycosidic bond of adenosine.
abstract: Previous estimates of the rate of spontaneous cleavage of the glycosidic bond of adenosine were determined by extrapolating the rates of the acid- and base-catalyzed reactions to neutral pH. Here we show that cleavage also proceeds through a pH-independent mechanism. Rate constants were determined as a function of temperature at pH 7 and a linear Arrhenius plot was constructed. Uncatalyzed cleavage occurs with a rate constant of 3.7x10(-12)s(-1) at 25 degrees C, and the rate enhancement generated by the corresponding glycoside hydrolase is approximately 5x10(12)-fold.
authors.affiliation: Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, 27599, United States.
authors.forename: Randy B
authors.initials: RB
authors.lastname: Stockbridge
authors.forename: Gottfried K
authors.initials: GK
authors.lastname: Schroeder
authors.forename: Richard
authors.initials: R
authors.lastname: Wolfenden
mesh_terms: D000241:Adenosine / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics
chemical_list: D000241:Adenosine