Comments
Blasticidin S belongs to the nucleoside antibiotics and has been isolated from Streptomyces griseochromogenes. It inhibits the protein synthesis in prokaryotes and eukaryotes by preventing the formation of the peptide binding. Meanwhile, several blasticidin-resistance genes have been isolated (one acetyl transferase [bls] and two deaminases [bsr and BSD]. The genes coding for the deaminases are used as selection markers.Blasticidin S hydrochloride is soluble in water or buffers (e. g. HEPES). The working concentration depends on the organism choosen. For E. coli a concentration of 50 - 100 μg/ml blasticidin S is applied, for mammalian cells only 3 to 10 μg/ml, in a few cases up to 30 μg/ml. Since the informations vary, it is recommended to determine the correct concentration for each cell line or organism. It is worth mentioning that high salt concentrations will inactivate blasticidin S. Therefore, for the selection of blasticidin S-resistant E. coli, the sodium chloride concentration has to be lowered from 10 to 5 g/L in LB broth / LB agar (10 g tryptone, 5 g yeast extract, 5 g NaCl per litre for the medium; additionally 15 g/L agar for the plates). Alternatively, the blasticidin concentration can be raised.Stability: Blasticidin S hydrochloride is shipped at ambient temperature and should be stored refrigerated upon arrival. The dry substance is stable for at least 2 years. It is recommended to filter-sterilize the solutions. A stock solution is prepared at a concentration of 50 mg/ml. The pH value should not exceed pH 7, because of inactivation of blasticidin S. Solutions are stable for approx. 2 weeks at \+4°C and frozen (-20°C) for approx. 2 months. Do not repeatedly freeze/thaw solutions.
