Penicillins are a class of antibiotics that have revolutionized the field of medicine since their discovery by Sir Alexander Fleming in 1928. These antibiotics are characterized by the presence of a beta-lactam ring in their molecular structure, which is essential for their antimicrobial activity. The most well-known and widely used penicillin is penicillin G, also known as benzylpenicillin. Penicillins exert their antibacterial effects by inhibiting the synthesis of bacterial cell walls. They target enzymes involved in the cross-linking of peptidoglycans, essential components of bacterial cell walls. This interference leads to weakened cell walls, ultimately causing bacterial cell lysis and death. The specificity of penicillins for bacterial cells over mammalian cells is attributed to differences in cell wall structure. Over the years, various derivatives and semi-synthetic penicillins have been developed to enhance their spectrum of activity and resistance to bacterial enzymes that degrade penicillins. These antibiotics are effective against a broad range of bacteria, making them a frontline treatment for various infections, from respiratory to skin infections. However, the widespread use of penicillins has led to the emergence of antibiotic-resistant strains of bacteria, highlighting the ongoing challenge of antibiotic stewardship in healthcare.
