Translation and Antibiotics

Antibiotics are drugs that kill bacteria. To make an effective antibiotic—not just any poison will do—the trick is to kill the bacteria without harming the patient.

Translation is frequently the target of antibiotics because it is essential to all living organisms and differs significantly between bacterial and eukaryotic cells. A number of antibiotics bind selectively to bacterial ribosomes and inhibit specific steps in translation, but they do not affect eukaryotic ribosomes. Tetracyclines, for instance, are a class of antibiotics that bind to the A site of a bacterial ribosome and block the entry of charged tRNAs, yet they have no effect on eukaryotic ribosomes. Chloramphenicol binds to the large subunit of the ribosome and blocks peptide-bond formation. Streptomycin binds to the small subunit of the ribosome and inhibits initiation, and erythromycin blocks translocation. Although chloramphenicol and streptomycin are potent inhibitors of translation in bacteria, they do not inhibit translation in archaea. Because different antibiotics block different steps in protein synthesis, antibiotics are frequently used to study protein synthesis.

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