Antibiotics that inhibit bacterial protein synthesis bind to bacterial ribosomes in ways that are distinct from their binding to eukaryotic ribosomes, which explains their specificity. The antibiotic chloramphenicol specifically targets the bacterial 50S ribosomal subunit, whereas aminoglycosides such as spectinomycin specifically target the bacterial 30S ribosomal subunit. Bacterial resistance to aminoglycosides is a major health problem, and this has led researchers to search for next-generation antibiotics. One class of these new antibiotics is called odilorhabdins, which are produced by symbiotic bacteria that live inside parasitic nematodes. Odilorhabdins are pseudopeptides that bind to a unique site in the 30S bacterial ribosome and, like aminoglycosides, cause errors in tRNA binding and misreading of the mRNA transcript.