Kanamycin sulfate is an aminoglycoside antibiotic commonly employed in molecular biology research for selecting recombinant bacteria It targets bacterial protein synthesis through binding to the bacterial 70S ribosomes effectively inhibiting peptide synthesis and thus preventing growth of non-resistant cells This solution contains kanamycin sulfate dissolved in sterile water at a concentration of 50 mg/ml supplied as a 1000X stock In molecular cloning experiments it is typically diluted to a working concentration of 50 g/ml in liquid or agar-solidified growth media for selective propagation of plasmid-transformed Escherichia coli strains such as DH5 (genotype F 80lacZ M15 (lacZYA-argF)U169 recA1 endA1 hsdR17 deoR supE44 thi-1 gyrA96 relA1) known for high efficiency transformation rates ( 10 8 cfu/ g plasmid DNA) Additionally this solution may also be incorporated as an antimicrobial agent in cell cultures to control bacterial contamination