Chloramphenicol

First isolated from a soil actinomycete in 1947, chloramphenicol was widely used as a broad-spectrum antibiotic although its clinical use has been curtailed because of drug-induced bone-marrow toxicity and the emergence of bacterial chloramphenicol resistance. Chloramphenicol inhibits the activity of ribosomal peptidyl transferase and thus inhibits protein synthesis (17). Chloramphenicol resistance is conferred by chloramphenicol acetyl transferase (cat), which transfers an acetyl group from acetyl CoA to chloramphenicol and inactivates it (18).