Chloramphenicol

Chemical structure: phenicole

Chloramphenicol is a synthetic antibiotic, isolated from strains of Streptomyces venezuelae. It is often used for bacterial selection in molecular biology applications at 10-20 μg/mL and as a selection agent for transformed cells containing chloramphenicol reistance genes.

Modo de acción: Inhibe la traducción en las subunidades de ribosomas 50S en la peptidiltransferasa (inhibición de elongación). Bacteriostático.
Modo de resistencia: Acetilación por cloranfenicol-acetiltransferasa (gen cat).

Stock solutions can be prepared directly in the vial at any recommended concentration. A solution at 50 mg/mL in ethanol yields a clear, very faint, yellow solution. Degradation of chloramphenicol in aqueous solution is catalyzed by general acids and bases. This rate of degradation is independent of the ionic strength and pH.

Stock solutions should be stored at 2-8°C and are stable at 37°C for 5 days. Aqueous solutions are neutral and stable over a wide pH range, with 50% hydrolysis occurring after 290 days. Use of a borax buffered solution reduces this number to 14%. Solutions should be protected from light as photochemical decomposition results in a yellowing of the solution. Heating aqueous solutions at 115°C for 30 minutes results in a 10% loss of chloramphenicol.