Pepsin, an enzyme that hydrolyzes peptide bonds in proteins, functions in the stomach at a pH optimum of 1.5 to 2.0. How is the rate of a pepsin-catalyzed reaction affected by each of the following conditions?
a. increasing the concentration of proteins

Question

Pepsin, an enzyme that hydrolyzes peptide bonds in proteins, functions in the stomach at a pH optimum of 1.5 to 2.0. How is the rate of a pepsin-catalyzed reaction affected by each of the following conditions?
a. increasing the concentration of proteins

a. increasing the concentration of proteins

Accepted Answer

All. Hello everyone. So this question says that trypsin is an enzyme that hydrolyzes proteins by cutting off peptide bonds functioning optimally in the small intestine at a ph of 7.5 to 8.5. How would increasing the concentration of proteins affect the rate of a reaction catalyzed by trypsin select all that apply. So here we have four different statements which we'll go through in greater detail later on and four different answer choices labeled A through D proposing which of these statements are correct. Now, let's understand the relationship that we're given, right. The enzyme that we're dealing with here is Trypsin and proteins in general are the substrate of trypsin. Why? Because trypsin is acting on proteins. So proteins are the compound undergoing the reaction here. So let's say I have a graph and on the x axis, let's say that I have the concentration of substrate and on the y axis, we have the activity of the enzyme. In other words, the rate of the reaction that the enzyme is catalyzing. What's important to recognize is that the concentration of the enzyme, the concentration of trypsin is staying the same. What's increasing is the substrate concentration. And so as the amount of the substrate increases, the enzyme is going to begin to act on the substrate and catalyze the reaction, this results in an initial increase in activity. But eventually because the concentration of the enzyme is not changing, you're going to reach a plateau. So in other words, enzyme activity increases only up to a certain point because as soon as you reach the plateau and the graph you have reached the saturation point of the enzyme. So the reason why activity of the enzyme stops increasing is because by this point, all of the molecules of your enzyme are occupied with substrate occupied with proteins here. And so if you don't increase the concentration of the enzyme, increasing, the concentration of the substrate won't change anything either because all of the enzyme molecules that you have are occupied already. So with this context in mind, with this little graph here, let's start with statement number one which reads that the reaction rate will increase as the concentration of proteins increases up to a point where the enzyme becomes saturated. Statement. One is correct, right? Because as mentioned before, until you reach the point where all of your enzyme molecules are occupied, then the concentration of the substrate will cause an increase in the activity of the enzyme statement. Two, on the other hand says that the reaction rate will remain constant regardless of changes in protein concentration. Once all enzyme active sites are occupied. This is also true, right? Because if the concentration of the enzyme is not also increasing, then increasing the concentration of the substrate won't change. The fact that all enzyme molecules are occupied. Statement three says that the reaction rate will plateau as the enzyme becomes fully saturated and cannot process additional substrate molecules. This is also correct because as mentioned before, this is the point where the enzyme becomes saturated with substrate. And last but not least statement four says that the reaction rate will decrease as excess proteins might interfere with the enzymes activity. Now, statement four is the only one that's not correct here because state four almost implies that the proteins, the excess proteins behave as a kind of competitive inhibitor. That's not necessarily true. Excess protein excess substrate generally isn't going to interfere with enzyme activity under normal conditions. The main point is that the reaction rate, the enzyme activity cannot increase any further because all enzyme molecules are occupied. So here of the four statements, numbers 12 and three are correct, which means that option c is correct and is our answer and there you have it. So with that being said, thank you so very much for watching and I hope you found this helpful.

Pepsin, an enzyme that hydrolyzes peptide bonds in proteins, functions in the stomach at a pH optimum of 1.5 to 2.0. How is the rate of a pepsin-catalyzed reaction affected by each of the following conditions?
a. increasing the concentration of proteins

Verified video answer for a similar problem:

Key Concepts

Enzyme Catalysis

Substrate Concentration

Michaelis-Menten Kinetics

Pepsin, an enzyme that hydrolyzes peptide bonds in proteins, functions in the stomach at a pH optimum of 1.5 to 2.0. How is the rate of a pepsin-catalyzed reaction affected by each of the following conditions?a. increasing the concentration of proteins

Verified video answer for a similar problem:

Key Concepts

Enzyme Catalysis

Substrate Concentration

Michaelis-Menten Kinetics

Pepsin, an enzyme that hydrolyzes peptide bonds in proteins, functions in the stomach at a pH optimum of 1.5 to 2.0. How is the rate of a pepsin-catalyzed reaction affected by each of the following conditions?
a. increasing the concentration of proteins