Question

26. The following experimental data were collected during a study of the catalytic activity of an intestinal peptidase with the substrate glycylglycine (Glycylglycine + H20 glycine). Use graphical analysis to determine the Vmax and Kn for this enzyme preparation and substrate.

Answer 1

Vmax and Km can be determined using graphical analysis of experimental data. Vmax is determined by plotting reaction rate against substrate concentration, and Km is determined by plotting the inverse of reaction rate against the inverse of substrate concentration.

Step-by-step explanation:

The kinetic parameters Vmax and Km can be determined using graphical analysis of the experimental data.

To determine Vmax, plot the reaction rate against substrate concentration. At high substrate concentrations, the active sites of all enzyme molecules are bound to substrate molecules, resulting in a constant reaction rate. The maximum reaction rate observed in the graph represents Vmax.

To determine Km, plot the inverse of reaction rate (1/V) against the inverse of substrate concentration (1/[S]). The x-intercept of the line represents -1/Km.

Answer 2

To determine the Vmax and Km for the enzyme preparation and substrate, perform graphical analysis using the experimental data collected. Plot the substrate concentration and reaction rate, create a double-reciprocal plot, perform linear regression analysis, and calculate Vmax and Km using the slope and y-intercept.

Step-by-step explanation:

In order to determine the Vmax and Km for the enzyme preparation and substrate, we need to perform graphical analysis using the experimental data collected. The Vmax represents the maximum rate of reaction when all enzyme active sites are saturated with substrate, while the Km represents the substrate concentration at which the reaction rate is at half of Vmax.

1. Plot the substrate concentration on the x-axis and the reaction rate on the y-axis.
2. Create a double-reciprocal plot by taking the reciprocal of both the substrate concentration and the reaction rate values.
3. Perform linear regression analysis on the double-reciprocal plot to obtain the slope and y-intercept.
4. The slope is equal to Km / Vmax, and the y-intercept is equal to 1 / Vmax.
5. Calculate Vmax by taking the reciprocal of the y-intercept.
6. Calculate Km by dividing the slope by Vmax.