Description_x000D_ General description_x000D_ Chemical structure: phenicole_x000D_ Application_x000D_ Chloramphenicol is a synthetic antibiotic, isolated from strains of Streptomyces venezuelae. It is often used for bacterial selection in molecular biology applications at 10-20μg/mL and as a selection agent for transformed cells containing chloramphenicol reistance genes._x000D_ Chloramphenicol has been used as a bacteriostatic non potent antibiotic. It has been used for the selection/growth of positive bacterial cells._x000D_ Packaging_x000D_ 1 kg in poly bottle_x000D_ 5, 25, 100, 500 g in poly bottle_x000D_ Biochem/physiol Actions_x000D_ Mode of Action: Chloramphenicol inhibits bacterial protein synthesis by blocking the peptidyl transferase step by binding to the 50S ribosomal subunit and preventing attachment of aminoacyl tRNA to the ribosome. It also inhibits mitochondrial and chloroplast protein synthesis and ribosomal formation of (p)ppGpp, de-pressing rRNA transcription._x000D_ Mode of Resistance: Use of chloramphenicol acetyltransferase will acetylate the product and inactivate it._x000D_ Antimicrobial Spectrum: This is a broad spectrum antibiotic against gram-positive and gram-negative bacteria, and is used mainly for ophthalmic and veterinary purposes._x000D_ Caution_x000D_ 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._x000D_ Preparation Note_x000D_ 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._x000D_ Other Notes_x000D_ Keep container tightly closed in a dry and well-ventilated place.