I'm doing enzyme immobilization right now and I want to calculate the effectiveness factor, η based on this formula:
η =Vmax of immobilized enzyme/Vmax of free enzyme
Vmax to be put inside the formula above must come from one substrate concentration. But how to calculate Vmax from only one concentration of substrate? Because the usual way that I know, to calculate kinetic data including Km, Vmax, a varying substrate concentration is needed.
There's one paper I'm referring to and I don't know how they did that.
Is there any other way to calculate effectiveness factor?
You ae quite correct about Vmax being determined with activity measurements at several concentrations. Presumably, the authors of the maper you mention had previous knowledge of the Km of the enzyme, thus if they choose a substrate concentration way above the Km, they know that the activity is close to Vmax
Pierre Béguin is probably right. However, for the sake of completeness, there is a way of measuring the kinetic parameters with a single substrate concentration (although it is still better to use several concentrations). This is progress curve analysis, in which the reaction is followed past the point at which it is running at the initial velocity, until it slows down due to substrate depletion. This curve is then fit by nonlinear regression to the integrated form of the Michaelis-Menten equation to obtain best-fit values of Km and Vmax.
- Badges
- Science topic
- Similar topics
- Biological Science
- Biochemistry
- Enzymology
- Enzymes