Ideally, an antibiotic should focus on a microbial target not found in mammalian cells. By this standard, which of the following antibiotic agents would be expected to be most toxic to humans?
Penicillin
Mitomycin
Cephalosporin
Bacitracin
Ideally, antibiotics should attack a microbial structure or function not found in human cells. Except for mitomycin, all the antibiotics listed in the question interfere with cell-wall synthesis in bacteria. Mitomycin inhibits DNA synthesis in both mammalian and microbial systems; viral DNA synthesis, however, is relatively resistant to mitomycin.
General