-You have discovered an enzyme that can catalyze two different chemical reactions. Which of the following is most likely to be correct?
A) The enzyme contains α-helices and β-pleated sheets.
B) The enzyme is subject to competitive inhibition and allosteric regulation.
C) Two types of allosteric regulation occur: The binding of one molecule activates the enzyme, while the binding of a different molecule inhibits it.
D) Either the enzyme has two distinct active sites or the reactants involved in the two reactions are very similar in size and shape.

Question

-You have discovered an enzyme that can catalyze two different chemical reactions. Which of the following is most likely to be correct?
A) The enzyme contains α-helices and β-pleated sheets. 
B) The enzyme is subject to competitive inhibition and allosteric regulation. 
C) Two types of allosteric regulation occur: The binding of one molecule activates the enzyme, while the binding of a different molecule inhibits it. 
D) Either the enzyme has two distinct active sites or the reactants involved in the two reactions are very similar in size and shape.

Quizplus · Accepted Answer

Enzymes that catalyze two different chemical reactions either have two distinct active sites to accommodate different substrates or the substrates for the two reactions are very similar in size and shape, allowing them to fit into the same active site. This is a fundamental principle of enzyme specificity and catalysis.

-You Have Discovered an Enzyme That Can Catalyze Two Different