Sulfa antibiotics damage bacteria by affecting a certain bacterial enzyme. The sulfa antibiotic looks similar to a substrate normally required by the bacterial cells to live. The sulfa antibiotic occupies the active site of the required enzyme and blocks entry of its normal substrate. This prevents the bacteria from making nucleotides that are required for their reproduction and survival. Based on this information, the action of sulfa antibiotics is an example of
A) activation energy.
B) competitive inhibition.
C) denaturing of proteins.
D) electron carriers.

Question

Quizplus · Accepted Answer

Sulfa antibiotics act as competitive inhibitors by resembling the natural substrate of an enzyme and binding to its active site, thereby preventing the actual substrate from binding and the enzyme from performing its normal function. This inhibits bacterial growth and reproduction.

Sulfa Antibiotics Damage Bacteria by Affecting a Certain Bacterial Enzyme