Enzyme Rate of Reaction Trypsin

Summary

This video demonstrates a practical investigation on how temperature affects the rate of an enzyme-controlled reaction, using trypsin, a protease enzyme. The enzyme breaks down casein in powdered milk, and the experiment measures the time it takes for the reaction to complete at different temperatures. The results show how reaction rates increase with temperature up to an optimum point (around 40°C), after which the rate decreases due to enzyme denaturation. This practical experiment helps illustrate the relationship between enzyme activity and temperature, providing insights into enzyme kinetics and the importance of temperature in biological processes.

Takeaways

• 😀 The experiment investigates the effects of temperature on the rate of an enzyme-controlled reaction, specifically using the protease enzyme trypsin.
• 😀 Trypsin is involved in the hydrolysis of peptide bonds in proteins, such as those in milk (casine), to form smaller, more soluble peptides.
• 😀 The experiment uses powdered milk as a substrate and measures how trypsin breaks down casine into soluble peptides and a fibrous protein that settles out.
• 😀 A water bath is prepared to maintain a temperature of 40°C to ensure the solutions reach the required temperature before starting the experiment.
• 😀 Two test tubes are labeled: 'T' for the test tube containing trypsin and 'C' for the control tube without trypsin, both containing powdered milk solution.
• 😀 pH 7 buffer is added to both test tubes, with the test tube labeled 'T' also receiving trypsin solution.
• 😀 The test tubes are placed in the water bath for 5 minutes to ensure the solutions reach 40°C before mixing the enzyme and milk.
• 😀 The experiment starts once the enzyme is added to the milk, and the timer is started. The goal is to observe when the X-mark on the test tube becomes visible.
• 😀 The end point of the experiment is when the X-mark becomes visible through the solution, signaling the completion of the reaction.
• 😀 The experiment is repeated at different temperatures, and the reaction rate is calculated by dividing the total reaction by the time taken, allowing the impact of temperature on the enzyme reaction rate to be analyzed.

Q & A

What is the aim of the experiment outlined in the script?

The aim of the experiment is to investigate the effect of temperature on the rate of an enzyme-controlled reaction, using tripsin to break down the protein casine in powdered milk.

What enzyme is used in the experiment and what is its function?

The enzyme used is tripsin, a protease enzyme that hydrolyzes peptide bonds in proteins, breaking them down into smaller peptides. It also causes milk protein (casine) to coagulate.

Why is powdered milk solution used as the substrate in this experiment?

Powdered milk solution is used because it contains the protein casine, which tripsin can break down, making it a suitable substrate for the experiment.

How is the temperature controlled during the experiment?

The temperature is controlled by using a water bath set to a specific temperature (initially 40°C). The test tubes are placed in the water bath to ensure the enzyme and substrate are at the desired temperature before starting the reaction.

What is the purpose of the control test tube labeled 'C'?

The control test tube labeled 'C' contains powdered milk solution and pH7 buffer but no tripsin enzyme. It serves as a baseline to compare the effect of tripsin in the experimental tube (labeled 'T').

What is the endpoint of the reaction, and how is it determined?

The endpoint of the reaction is when the cross marked on the back of the test tube becomes visible through the solution, indicating that the protein has coagulated and the reaction is complete.

What role does the pH7 buffer play in the experiment?

The pH7 buffer maintains a stable pH environment in the reaction, ensuring that the enzyme tripsin remains active and functions optimally.

What is the significance of performing the experiment at various temperatures?

Performing the experiment at various temperatures allows the observation of how temperature affects the rate of the enzyme-controlled reaction, helping to identify the optimum temperature for tripsin activity.

How do you calculate the rate of the reaction in this experiment?

The rate of reaction is calculated by dividing the total reaction time by the time it took for the cross to become visible, and the result is often expressed in standard form (e.g., seconds × 10^-3).

What is the expected outcome of the experiment in terms of enzyme activity?

The expected outcome is that the reaction rate will increase with temperature up to an optimum point (around 40°C), after which higher temperatures may reduce the reaction rate due to enzyme denaturation.