What is the primary mode of action of antibiotics like penicillin?

What is the primary mode of action of antibiotics like penicillin?

• A. Inhibit nucleic acid synthesis
• B. Disrupt metabolic pathways
• C. Inhibit cell wall synthesis
• D. Inhibit protein synthesis

Answer: (C)

The primary mode of action of antibiotics like penicillin is to inhibit cell wall synthesis. Penicillin specifically targets the bacterial cell wall, which is essential for the structural integrity and stability of bacteria. During cell division, penicillin interferes with the enzymes responsible for cross-linking the peptidoglycan layers in the cell wall. This disruption prevents bacteria from forming a proper cell wall, leading to cell lysis and ultimately the death of the bacteria, particularly in actively dividing cells. In contrast, other antibiotics may work through different mechanisms. Some drugs inhibit nucleic acid synthesis, which interferes with the bacterial DNA replication or RNA transcription processes. Others might disrupt metabolic pathways, affecting essential biochemical processes necessary for growth and survival. Meanwhile, some antibiotics inhibit protein synthesis by targeting bacterial ribosomes, which are essential for translating genetic information into functional proteins. Penicillin’s unique action on the cell wall distinguishes it and explains why it is particularly effective against certain types of bacteria, especially Gram-positive strains.

The primary mode of action of antibiotics like penicillin is to inhibit cell wall synthesis. Penicillin specifically targets the bacterial cell wall, which is essential for the structural integrity and stability of bacteria. During cell division, penicillin interferes with the enzymes responsible for cross-linking the peptidoglycan layers in the cell wall. This disruption prevents bacteria from forming a proper cell wall, leading to cell lysis and ultimately the death of the bacteria, particularly in actively dividing cells.

In contrast, other antibiotics may work through different mechanisms. Some drugs inhibit nucleic acid synthesis, which interferes with the bacterial DNA replication or RNA transcription processes. Others might disrupt metabolic pathways, affecting essential biochemical processes necessary for growth and survival. Meanwhile, some antibiotics inhibit protein synthesis by targeting bacterial ribosomes, which are essential for translating genetic information into functional proteins. Penicillin’s unique action on the cell wall distinguishes it and explains why it is particularly effective against certain types of bacteria, especially Gram-positive strains.