With a convenient one-step supplementation Penicillin/Streptomycin with L-Glutamine helps researchers to save time while reducing risks for contamination caused by multiple invasive supplementation schedules. The antibiotics penicillin and streptomycin are used in cell culture to prevent bacterial contamination due to their effective combined action against gram-positive and gram-negative bacteria. Penicillin acts by interfering with the turnover of the bacterial cell wall. Streptomycin acts by binding to the 30S subunit of the bacterial ribosome, leading to inhibition of protein synthesis and death in susceptible bacteria. L-Glutamine is an essential amino acid and is a crucial component of culture media. It serves as a major energy source for cells in culture. Penicillin/Streptomycin with L-Glutamine is provided as a ready to use 100x concentrate.