Enzymes

Question 1

Define metabolic pathway.

Answer 1

It is a series of enzyme catalyzed reactions in which the product formed is the substrate for the next reaction.

Question 2

What are the different amino acids and its functions?

Answer 2

Contact amino acids: specificity of the enzyme and forming a complementary shape to the substrate to fit.
Catalytic amino acids: catalyze a metabolic reaction
Non-essential amino acids: no specific function
Structural amino acids: maintain the overall 3D conformation

Question 3

What is the mechanism of enzyme action.

Answer 3

1. When a substrate molecule happens to collide with the active site of a enzyme molecule at the right orientation , the enzymes active site will bind with the substrate molecule.
2. Binding of the enzymes active site with the substrate will cause a conformational change to better fit the substrate.
3. The enzymes active site is now complementary in shape to the substrate molecule. The R-groups of the amino acids interact with the substrate in a chemically attractive manner.
4. An enzyme-substrate complex is thus formed.
5. The enzymes contact amino acids will hold the substrate in an orientation that favours the reaction to happen.
6. Specific spatial awareness of the substrate molecule at the active site will physical stress to the bonds.
7. The R-groups of catalytic amino acids can also change the charge on the substrate molecule to increase the reactivity of the substrate molecule
8. Hence , enzymes lower the initial amount of energy required for product formation.

Question 4

What happens to enzymes when the temp is past the optimum lvl

Answer 4

Disruption of weak bonds that maintain the 3D conformation like hydrogen bonds , ionic bonds and hydrophobic interactions. This causes the enzyme to lose its secondary and tertiary structure , leading to loss of enzymes active site.

Question 5

What happens when pH level is below/above the optimum pH level?

Answer 5

Changes in concentration of H+ and OH- alters ionic charges of acidic and basic R groups of amino acids. This disrupts the ionic and hydrogen bonds that maintain the 3D conformation and active site of the enzyme. `

Question 6

What is an inhibitor?

Answer 6

An inhibitor is a substance that prevents an enzyme from catalyzing its reaction.

Question 7

What is an allosteric enzyme?

Answer 7

it is an enzyme whose activity can be altered by binding of a regulatory enzyme to its allosteric site.

Question 8

What are co-factors?

Answer 8

No-protein components required for the activities of certain enzymes.