While a broad interpretation of this definition could be used to describe nearly any compound depending on concentration, in practice, it usually refers to compounds that act at the molecular level on translational machinery (either the ribosome itself or the translation factor),[2] taking advantages of the major differences between prokaryotic and eukaryotic ribosome structures.
The following antibiotics bind to the 30S subunit of the ribosome:
The following antibiotics bind to the 50S ribosomal subunit: