Application Used together with penicillin and other agents to inhibit bacterial contamination in cell culture applications. Biochem/physiol Actions Mode of Action: Inhibits prokaryote protein synthesis. Binds to S12 protein of 30S ribosomal subunit, preventing the transition from initiation complex to chain-elongating ribosome, causing miscoding or inhibiting initiation. Mode of Resistance: Mutation in rpsL (gene for S12 ribosomal protein) prevents binding of streptomycin to ribosome. Aminoglycoside phosphotransferase also inactivates.Antimicrobial spectrum: Gram-negative and Gram-positive bacteria.