4.4 Cofactors, Coenzymes, And Prosthetic Groups

Question 1

What are cofactors?

Answer 1

• non-protein component that help enzymes carry out their function
• inorganic cofactors are obtained via the diet as mineral se.g. Iron, calcium, chloride and zinc ions

Question 2

What are coenzymes?

Answer 2

• organic molecule
• derived from vitamins
• they help enzymes carry out their function

Question 3

What are prosthetic groups?

Answer 3

Cofactors - they are required by retain enzymes to carry out their catalytic function
- while some cofactors are loosely or temporarily bound to the enzyme protein, prosthetic groups are tightly bound and permanent

Question 4

What is precursor activation?

Answer 4

Precursor enzymes are inactive and need to undergo a change in shape (tertiary structure), particularly to the active site to e activated
This can be achieved y the addition of a cofactor
Before cofactor is added, the precursor protein is called an apoenzyme. When the cofactor is added and the enzyme is activated, it is called a haloenzyme