Puromycin Puromycin is an aminonucleoside antibiotic produced by Streptomyces alboniger. It specifically inhibits peptidyl transfer on both prokaryotic and eukaryotic ribosomes. This antibiotic inhibits the growth of Gram positive bacteria and various animal and insect cells. Puromycin can also be used in some particular conditions for the selection of E. coli transformants. Resistance to puromycin is conferred by the Pac gene encoding a puromycin N-acetyl-transferase (PAC) that was found in a Streptomyces producer strain. Animal cells are generally sensitive to concentrations from 1 to 10 µg/ml. Working concentration:1 to 10 µg/ml in animal cells CAS number: 58-58-2 Purity: >95% Molecular weight: 471.51 Formula: C22H29N7O5, 2HCl