The activity of pepsin was measured at various pH values....

Name: Problem 17, Chapter 22: Introduction to General, Organic and Biochemistry
Uploaded: 2021-01-24T04:25:52-08:00
Duration: 3 min 43 s
Channel: Sandra Lundell
Description: The activity of pepsin was measured at various pH values. When the temperature and the concentrations of pepsin and substrate were held constant, the following activities were obtained: (a) Plot the pH dependence of pepsin activity. (b) What is the optimal pH? (c) Predict the activity of pepsin in the blood at pH 7.4

The activity of pepsin was measured at various pH values. When the temperature and the concentrations of pepsin and substrate were held constant, the following activities were obtained: (a) Plot the pH dependence of pepsin activity. (b) What is the optimal pH? (c) Predict the activity of pepsin in the blood at pH 7.4

The activity of pepsin was measured at various pH values. When the temperature and the concentrations of pepsin and substrate were held constant, the following activities were obtained: (a) Plot the pH dependence of pepsin activity.
(b) What is the optimal pH?
(c) Predict the activity of pepsin in the blood at pH 7.4

Key Concepts

Optimal pH

The optimal pH is the specific environmental pH at which an enzyme reaches its maximum catalytic efficiency. At this pH, the ionization state of the active site residues is ideal for substrate binding and catalysis, allowing for the highest reaction rate compared to pH levels that deviate from this optimum.

Effect of pH on Enzyme Structure

Enzymes rely on a delicate three-dimensional structure for proper function, and pH can influence this structure by altering the ionization of amino acid side chains. Changes in pH can disrupt hydrogen bonds and electrostatic interactions, leading to conformational changes that decrease enzyme stability and activity.

Enzyme Activity vs pH Profile

This concept describes how an enzyme’s catalytic activity varies as a function of pH. Enzyme activity is plotted against pH to reveal a bell-shaped curve, where the enzyme performs optimally at a specific pH level and exhibits reduced activity as the pH moves away from this optimum due to alterations in the enzyme's ionization states and conformation.

Transcript

Please give Ace some feedback