Which antibiotic class primarily targets the 30S ribosomal subunit to inhibit protein synthesis?

The antibiotic class that primarily targets the 30S ribosomal subunit to inhibit protein synthesis is the aminoglycosides. These agents, which include drugs like gentamicin and amikacin, bind to the 30S subunit of bacterial ribosomes, leading to misreading of mRNA. This misreading results in the incorporation of incorrect amino acids into the growing peptide chain, ultimately inhibiting bacterial protein synthesis and leading to cell death.

In contrast, macrolides act on the 50S ribosomal subunit, inhibiting protein synthesis by blocking the exit tunnel for the growing peptide chain, while beta-lactams target bacterial cell wall synthesis rather than protein synthesis. Glycopeptides also do not inhibit protein synthesis; instead, they interfere with the synthesis of the bacterial cell wall by binding to D-alanyl-D-alanine precursors. Thus, the specificity of aminoglycosides for the 30S ribosomal subunit is what makes them the correct answer in this context.