Question

This is a very simpllistic approach to protein folding, which ignores solvent and volume effects, but it allows us to practice what we have learned about thermodynamics and kinetics. Enzymes are long chains of amino acids that have to fold in the proper way so as to exhibit enzyme activity. They can catalyze certain reactions. Let us pick a reaction in the human body at 37 C, we will call it enzyme X.

Let's say that enzyme X is the catalyst responsible for breaking starch down to individual glucose molecules. What of the following things can happen to the starch and enzyme system if you rainse the temperature?

a-the rate of the reaction of starch going to glucose will increase

b-nothing should happen since a catalyst does not affect the equilibrium

c-the enzyme could stop working effectively becauset the folded form would stop being made and would start to unravel if the process is reversible

d-the equilibrium constant will get bigger to favor the glucose side more

Answer 1

Here (c) would be the correct answer i.e. the enzyme could stop working effectively because the folded form would stop being made and would start to unravel if the process is reversible. Because enzyme action in our body is temperature and P^H dependent. The enzyme activity is maximum at optimum temperature( normally the body temperature) and optimum P^H range( usually 5-7). Because at optimum temperature, they are in their right shape with proper folding of aminoacid chains catalysing the reaction at optimum rate.

However when the temperature is decreased, the enzyme becomes too tight losing its proper shape and hence decreases the enzyme activity. Also when the temperature is increased,the enzyme becomes too lose losing its shape. This also decreases the enzyme to a great extent. If the temperature increase or decrease it too large, the enzyme becomes denatured losing its function completely.