What is the mechanism of action of cephalosporins?

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Multiple Choice

What is the mechanism of action of cephalosporins?

Cephalosporins work by binding to penicillin-binding proteins, blocking the transpeptidase step needed to cross-link peptidoglycan in the bacterial cell wall. This weakens the cell wall as the bacterium grows, leading to lysis and death—so they are bactericidal. This mechanism is a hallmark of beta-lactam antibiotics, similar to penicillins, though cephalosporins often have different stability to certain beta-lactamases and a broader spectrum in some generations. Other actions listed belong to different antibiotic classes: disrupting the cell membrane is characteristic of agents like polymyxins or daptomycin; inhibiting DNA replication is the domain of fluoroquinolones; inhibiting protein synthesis at the 50S subunit is seen with macrolides and related drugs.

Cephalosporins work by binding to penicillin-binding proteins, blocking the transpeptidase step needed to cross-link peptidoglycan in the bacterial cell wall. This weakens the cell wall as the bacterium grows, leading to lysis and death—so they are bactericidal. This mechanism is a hallmark of beta-lactam antibiotics, similar to penicillins, though cephalosporins often have different stability to certain beta-lactamases and a broader spectrum in some generations.

Other actions listed belong to different antibiotic classes: disrupting the cell membrane is characteristic of agents like polymyxins or daptomycin; inhibiting DNA replication is the domain of fluoroquinolones; inhibiting protein synthesis at the 50S subunit is seen with macrolides and related drugs.

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