Option 3

Prof. Wilson: Well-done! This is correct! Remember that a substrate is the specific reactant molecule upon which an enzyme acts. It binds to the enzyme's active site, where the chemical reaction occurs. The active site is the region on an enzyme where the substrate binds. It is typically a pocket or groove on the enzyme's surface and facilitates the conversion of the substrate into the product. The active site contains specific amino acid residues that interact with the substrate. Finally, a product is the molecule or molecules that result from the enzymatic conversion of the substrate. It is released from the enzyme after the reaction is complete. Who can give me an example?

James: I remember the enzyme sucrase, which catalyzes sucrose, which is the substrate.  

You: That’s right, water is also utilized in the reaction, and fructose and glucose are the products of the reaction. The active site on the sucrase enzyme is specific for sucrose and no other substrates have the molecular structure to allow binding. 

Breakdown of sucrose (substrate) to fructose and glucose (product) catalysed by sucrase.

Website: https://commons.wikimedia.org/wiki/File:Sucrase.svg

You: Prof., how fast can an enzyme catalyze a reaction?

Prof. Wilson: Good question! Some key factors can affect the activity of the enzyme. Let’s see if you remember what we talked about in class this week.

Which factor can increase enzyme activity?