Gibco® Antibiotic-Antimycotic is used to prevent bacterial and fungal contamination. The combination of the antibiotics penicillin and streptomycin are used to prevent bacterial contamination of cell cultures due to their effective action against gram-positive and gram-negative bacteria, respectively. Fungizone® (amphotericin B) is used to prevent fungal contamination of cell cultures due to its inhibition of multi-cellular fungus and yeast.

Penicillin was originally purified from the fungus Penicillium and acts by interfering directly with the turnover of the bacteria cell wall and indirectly by triggering the release of enzymes that further alter the cell wall. Streptomycin was originally purified from Streptomyces griseus. Streptomycin acts by binding to the 30S subunit of the bacterial ribosome leading to inhibition of protein synthesis and death in susceptible bacteria. Fungizone® (amphotericin B) is an antifungal agent that prevents the growth of fungi and yeast by