Kinetics of Rat Liver Glucokinase CO-OPERATIVE INTERACIIONS WITH GLUCOSE AT PHYSIOLOGICALLY SIGNIFICANT CONCENTRATIONS By ANDREW C. STORER* and ATHEL CORNISH-BOWDEN
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چکیده
The kinetics of glucokinase from rat liver were studied over wide ranges of glucose and MgATP2concentrations. The initial rate shows a co-operative dependence on the glucose concentration, with Hill coefficients in the range 1.2-1.5. The degree of glucose co-operativity increases with the MgATP3concentration, but no co-operativity was detected for the dependence of the rate on the MgATP2concentration. The effects observed occur at physiologically reasonable concentrations of glucose and MgATP2and are consistent with the presumed function of glucokinase in maintaining a constant concentration of glucose in the blood.
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