Which antibiotic inhibits the 50S ribosomal subunit?

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Multiple Choice

Which antibiotic inhibits the 50S ribosomal subunit?

Macrolides inhibit the 50S ribosomal subunit by binding to the large ribosomal subunit and blocking the translocation step of protein synthesis. When the ribosome can’t move along the mRNA, elongation stops and the polypeptide chain cannot be completed. This specifically targets the 50S subunit's function in translation. In contrast, antibiotics that act on the 30S subunit, like tetracyclines and aminoglycosides, disrupt initiation and decoding by affecting tRNA attachment or causing misreading of mRNA. Rifampin works differently as well: it inhibits bacterial RNA polymerase, blocking transcription rather than translation. So the antibiotic that inhibits the 50S subunit is the macrolide class.

Macrolides inhibit the 50S ribosomal subunit by binding to the large ribosomal subunit and blocking the translocation step of protein synthesis. When the ribosome can’t move along the mRNA, elongation stops and the polypeptide chain cannot be completed. This specifically targets the 50S subunit's function in translation.

In contrast, antibiotics that act on the 30S subunit, like tetracyclines and aminoglycosides, disrupt initiation and decoding by affecting tRNA attachment or causing misreading of mRNA. Rifampin works differently as well: it inhibits bacterial RNA polymerase, blocking transcription rather than translation. So the antibiotic that inhibits the 50S subunit is the macrolide class.

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