Enzyme Kinetics and Inhibition: Key Concepts and Practice Questions

What is Vmax in enzyme reactions?

The maximum velocity at which an enzyme system can function.

What primarily causes the limited value (Vmax) of the reaction rate?

Saturation of the enzyme with substrate.

What does Penicillin interfere with in bacteria?

The synthesis of peptidoglycan.

What type of inhibitor is Penicillin?

An irreversible inhibitor of transpeptidase.

What should be the chirality of phenylalanine in Penicillin?

D-stereomer.

How do enzymes differ from other catalysts?

Enzymes display specificity toward a single reactant.

What is the correct statement about antigen-antibody interactions?

Antigens bind to antibodies through induced fit.

What is true about enzyme-catalyzed reaction?

the reaction is faster than the same reaction in the absence of the enzyme

What does (Vo) stand for in a reaction?

initial velocity

What is Km?

substrate concentration at 50% Vmax

What allows comparing an enzyme's preference for different substrates?

Dissociation constant.

What class of enzymes converts glucose into fructose?

Isomerases.

What is true of the binding energy from enzyme-substrate interactions?

It is sometimes used to hold two substrates in the optimal orientation for reaction.

What is an enzyme?

specialized biological molecules—mostly proteins—that act as catalysts to speed up chemical reactions in living things.

How does an uncompetitive inhibitor bind to an enzyme?

It reversibly binds to the enzyme-substrate complex but does not bind to the free enzyme.