Question

Match the columns and bring out the correct option of inhibitor and its effect.

a. Chloramphenicol	p. inhibits binding of aa-tRNA to ribosome
b. Erythromycin	q. inhibits the interaction between tRNA and mRNA
c. Neomycin	r. Inhibits initiation of translation
d. Streptomycin	s. Inhibits peptidyl transferase activity
e. Tetracycline	t. Inhibits translocation of mRNA over ribosome

A. a-p,b-q,c-r,d-t,e-s
B. a-r,b-p,c-t,d-s,e-q
C. a-q,b-r,c-s,d-p,e-t
D. a-s,b-t,c-q,d-r,e-p

Answer 1

Hint: The enzymes in our body play an important role in the functioning of the metabolism. They are the proteins which carry out the working of the metabolisms. They tend to regulate the amount of every substance in the body.

Complete answer:
The enzymes being the chemical messengers of the body can enhance or inhibit a function. So the enzymes which will inhibit any activity in the metabolism are called the inhibitors.
Chloramphenicol – It is bacteriostatic which inhibits the protein synthesis. It will inhibit the peptidyl transferase activity in the bacterial ribosome. This will prevent the protein chain elongation in the bacterias. (s)
Erythromycin – It is a bacteriostatic drug which will bind to the 50S complex of the ribosome. It will restrict the movement of the tRNA from the A site to the P site. Thus the chain elongation will stop and the tRNA will not be able to bind to the mRNA. The bacterial proteins will not be synthesized. (t)
Neomycin – It will bind to the 30S part of the ribosome thus preventing binding of the mRNA and rRNA. The important proteins are not synthesized thus the bacteria dies. (q)
Streptomycin – It is an antibiotic which will bind to the 16S subunit of the rRNA. This will disrupt the synthesis of methionyl tRNA which is essential for protein synthesis initiation. Thus the translation will not occur. (r)
Tetracycline – It is an antibiotic. It binds to A site of the rRNA. Thus it will not bind to the aminoacyl(aa) tRNA, this, in turn, will prevent the peptide chain elongation. (p)

Hence, the correct answer is option (D).

Note: They inhibit the enzyme’s active sites thus preventing it to form the substrate enzyme complex. This will reduce the enzyme’s compatibility to bind to the substrate. There can be competitive, non-competitive and mixed inhibitors.