Antibiotics Discovery, Mode of Action, and Mechanism of Resistance

Although antibiotics have revolutionized modern medicine, studies on their discovery, mechanisms of action, and the growing problem of resistance are still vital. Foundational work by pioneers such as Antonie van Leeuwenhoek, Joseph Lister, Louis Pasteur, and Robert Koch contributed significantly to the understanding of microorganisms and infectious diseases. The development of key antibiotics, including Penicillin, mycophenolic acid, synthetic Salvarsan, and Prontosil, marked significant medical advancements. In order to improve their clinical applications and output, researchers such as Andrew Moyer, Robert Coghill, Norman Heatley, Howard Florey, Ernst Chain, and Alexander Fleming were essential. Subsequent discoveries of antibiotics such as tyrothricin, streptomycin, chlortetracycline, and erythromycin further broadened treatment possibilities. Antibiotics primarily function by inhibiting cell wall synthesis, disrupting the membranes of bacterial cells, and interfering with vital biological functions like the synthesis of folic acid, DNA replication, transcription, and protein synthesis. However, resistance mechanisms—including modifications of penicillin-binding proteins, β-lactamase production, drug inactivation, reduced membrane permeability, efflux pump activity, and target site alterations—have complicated treatment effectiveness. Resistance can be innate or acquired, and its development is mostly influenced by genetic mutations and horizontal gene transfer. Human behaviors such as self-medication, improper prescription writing, and excessive use of antibiotics in agriculture all contribute to the development of resistance. The serious consequences of antibiotic resistance, which include increased hospital stays, increased medical expenses, increased mortality rates, and diminished efficacy in treating common illnesses, make it a significant global public health concern. Combating this growing issue necessitates the discovery of new antibiotics, stricter regulatory policies, enhanced diagnostic capabilities, and greater public awareness to curb the spread of resistance.