Penicillin and streptomycin are broad spectrum bacteriostatic and bacteriocidal agent effective against gram positive bacteria and gram negative bacteria. This product is a powdered antibiotic mixture formulated to contain 5000 units penicillin and 5mg streptomycin per ml when reconstituted with sterile tissue culture grade water to indicated level. Penicillin and streptomycin are broad spectrum bacteriostatic and bacteriocidal agent effective against gram positive bacteria and gram negative bacteria. Penicillin acts by inhibiting cell wall synthesis. Streptomycin blocks the initiation complex of protein synthesis by binding to the 30S subunit of bacterial 70S ribosome, thus interfering with the protein synthesis.