Question

60. What is an apoenzyme?
(A) It is a protein portion of an enzyme
(B) It is a non-protein group
(C) It is a complete, biologically active conjugated enzyme
(D) It is a prosthetic group

Answer 1

Answer:

C

Explanation:

Removal of cofactor from a conjugated enzymes forms apoenzyme which is a protein component.

Answer 2

Apoenzyme

Explanation:

• A protein that forms an active enzyme system by combination with a coenzyme and determines the specificity of this system for a substrate.
• Activation of the enzyme occurs upon binding of an organic or inorganic cofactor.
• Holoenzyme is an apoenzyme together with its cofactor.
• A holoenzyme is complete and catalutically active.
• Most cofactors are not covalently bound but instead are tightly bound.
• Thus  it is protein portion of an enzyme.