[05] Enzymes: Mechanism of Action Flashcards
What are enzymes?
Proteins that act as biological catalysts.
How do enzymes accelerate biochemical reactions?
By lowering the activation energy.
What is the substrate in enzymatic reactions?
The molecule upon which an enzyme acts.
What is the active site of an enzyme?
The region of an enzyme where substrate molecules bind and undergo a chemical reaction.
What is the enzyme-substrate complex?
The temporary complex formed when an enzyme binds to its substrate molecule(s).
What is enzyme specificity?
The concept that each enzyme catalyzes only one kind of reaction.
What affects enzyme activity?
- Temperature
- pH
- Substrate concentration
- Enzyme concentration
How does temperature affect enzyme activity?
Enzyme activity increases as temperature increases, until the enzyme denatures at high temperatures.
How does pH affect enzyme activity?
Each enzyme has an optimal pH at which its activity is highest.
What is a cofactor?
A non-protein chemical compound required for an enzyme’s activity.
What is a coenzyme?
An organic molecule serving as a cofactor. Most vitamins function as coenzymes.
What is enzyme inhibition?
A process in which a molecule binds to enzymes and inhibits their activity.
What are the two types of enzyme inhibitors?
- Competitive inhibitors
- Non-competitive inhibitors
What is a competitive inhibitor?
A substance that competes with the substrate for binding to the active site of the enzyme.
What is a non-competitive inhibitor?
A substance that binds to a site other than the active site, changing the shape of the enzyme and making it less effective.
