Concept:Many clinical drugs are designed as competitive inhibitors to specifically target and starve bacterial metabolic pathways.
Solution:- Sulphonamides (sulfa drugs) are a classic textbook example of competitive inhibition.
- They are structurally very similar to para-aminobenzoic acid (PABA), a natural substrate bacteria use to synthesize folic acid.
- The drug competitively binds to the bacterial enzyme instead of PABA, halting folic acid synthesis and killing the bacteria.
Why other options are incorrect:Cyanide is an irreversible, non-competitive inhibitor that binds strongly to cytochrome c oxidase. Insecticides (like organophosphates) and heavy metal ions generally form strong covalent bonds, acting as irreversible/non-competitive poisons.
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