Penicillin G potassium salt is a member of the penicillin class of antibiotics and is effective against a variety of gram-positive bacteria. As a narrow-spectrum antibiotic belonging to the beta-lactam class, it inhibits the synthesis of bacterial cell walls. It interferes with the formation of peptidoglycan, a crucial component of the bacterial cell wall. This weakens the cell wall and leads to the eventual rupture of the bacterial cell.
Penicillin G is effective against a wide range of Gram-positive bacteria, including Streptococcus, Staphylococcus, and some other species. However, it is not effective against Gram-negative bacteria due to their different cell wall structure.