Searching for Novel Antibiotics

The four common classes of antibiotics target (1) bacterial cell wall synthesis (penicillins), (2) bacterial nucleic acid synthesis (sulfonamides), (3) bacterial protein synthesis (chloramphenicol and aminoglycosides), and (4) bacterial cell membrane functions (polymyxins). Antibiotics that inhibit bacterial protein synthesis bind to and block the function of bacterial ribosomes but not eukaryotic ribosomes. Antibiotic resistance 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 bind to a unique site on the 16S rRNA of the 30S bacterial ribosome, where they interact with both the rRNA and the incoming aminoacyl-tRNA, causing misincorporation of amino acids during bacterial protein synthesis.