Question

1. Which enzyme uses general acid-base catalysis and or covalent catalysis mechanisms to hydrolyze peptidoglycan?

A. Enolase

B. lysozyme

C. chymotrypsin

D. pepsin

E. B-lactamase

2. the HIV protease enzyme uses a general acid-base catalysis mechanism to cleave viral polypeptides but does not use a covalent catalysis. This enzyme functions optimally in the pH range of 4-6. Due to the specific amino acids involved in this catalysis, HIV protease is a member of which subclass of proteases?

A. Metalloproteases

B. Serine proteases

C. aspartyl proteases

D. cysteine proteases

E. lysine proteases

3. If chemical reactions will eventually reach an equilibrium state, what is the purpose of enzymes in a biological system?

A. Enzymes are consumed to speed up chemical reactions

B. Enzymes speed up chemical reactions without being used up in the process

C. Enzymes slow down chemical reactions

D. Enzymes alter the equilibrium state between reactants and products

E. enzymes prevent the formation of unstable reaction intermediates

Answer 1

1. option B) Lysozome is the enzyme that uses general acid-base catalysis and or covalent catalysis mechanisms to hydrolyze peptidoglycan.

Bacterial cell walls contain a layer of peptidoglycan. The peptidoglycan layer contains alternating molecules known as N-acetylglucosamine and N-acetylmuramic acid. These molecules form a strong glycan chain that act as the backbone for the cell wall. The link between the N-acetylglucosamine and N-acetylmuramic acid is hydrolyzed and thereby cleaved by lysozyme.

2. HIV protease is a member of aspartyl proteases subclass.

Therefore, the correct option is C) aspartyl proteases.

3. Enzymes are biological catalysts or chemicals that speed up the rate of reaction and therefore speeds up chemical reactions without themselves being consumed in the reaction. This is usually decreasing the activation energy. Enzymes do not change the equilibrium state of a biochemical reaction.

Therefore, the correct option is B) Enzymes speed up chemical reactions without being used up in the process.