In summary, specific activity = enzyme units / (vol. in µl x (protein conc. in mg per ml / 1000))

How do you determine experimental Km and Vmax?

v = Vmax – Km x v / [S] plotting v against v / [S] gives a straight line: y intercept = Vmax. gradient = -Km. x intercept = Vmax / Km.

What is used to measure specific activity?

Specific activity is the activity per quantity of a radionuclide and is a physical property of that radionuclide. It is usually given in units of Bq/kg, but another commonly used unit of activity is the curie (Ci) allowing the definition of specific activity in Ci/g.

Why do Enzymologists determine specific activity?

Enzymologists determine specific activity in order to determine the purity of the enzyme sample mixture. As the enzyme becomes more pure in a mixture, the specific activity value increases. The expected range of the specific activity is known to be 0.05- 2.0 units/mg of protein.

What does specific activity tell you?

Specific activity gives a measurement of enzyme purity in the mixture. It is the micro moles of product formed by an enzyme in a given amount of time (minutes) under given conditions per milligram of total proteins.

What is the difference between activity and specific activity?

The main difference between enzyme activity and specific activity is that enzyme activity is the moles of substrate converted by the enzyme per unit time whereas specific activity is the activity of enzyme per milligram of total enzyme.

How do you calculate Vmax?

Ease of Calculating the Vmax in Lineweaver-Burk Plot Next, you will obtain the rate of enzyme activity as 1/Vo = Km/Vmax (1/[S]) + 1/Vmax, where Vo is the initial rate, Km is the dissociation constant between the substrate and the enzyme, Vmax is the maximum rate, and S is the concentration of the substrate.