Enzyme kinetics Demo
How inhibitors change an enzyme’s rate curve, and how a single feedback loop in glycolysis can make metabolite levels oscillate.
Enzyme
Inhibitor
Apparent Vmax0
Apparent Km0
Glycolytic oscillator
What it models
Steady-state rates of a single-substrate enzyme with a reversible inhibitor, and the Sel'kov model of phosphofructokinase, where the product ADP activates the enzyme that makes it. Inside the oscillatory range of a and b, the steady state loses stability and a limit cycle appears.
Method
- Rate curves are closed-form; the double-reciprocal plot uses the same parameters.
- The oscillator is integrated with fourth-order Runge–Kutta, Δt = 0.02.
- The oscillation label uses the model's Hopf boundary, b² = ½(1 − 2a ± √(1 − 8a)).
- Reference: Sel'kov, Eur. J. Biochem. 4:79 (1968).