The first antibiotic, penicillin G [P1772], was discovered and named by Alexander Fleming in 1928 when he observed that a fungus from the Penicillum family produces a material that has powerful antimicrobial activity. Therefore, the term "antibiotics" originally refers to a natural compound produced by a fungus or another microorganism that kills bacteria. With advances in medicinal chemistry, most antibiotics, also known as antimicrobial agents, are now semi-synthetic and modified chemically from original compounds found in nature. Other antibiotics are fully synthetic compounds named "synthetic antimicrobials".
Although there are a number of different types of antibiotics, they can be divided into two classes based on their mechanism of action: bactericidal and bacteriostatic antibiotics. A bactericidal antibiotic kills bacteria. It usually either interferes with the formation of the bacterium's cell wall or its cell contents. A bacteriostatic antibiotic prevents bacteria from multiplying by inhibiting its DNA replication or protein synthesis. Therefore, antibiotic reagents for research are widely used not only as targeted medications for the development of new antibiotics, but also as cell culture supplements to avoid bacterial contaminations, and as selective reagents for genetic studies designed to isolate organisms coupled to a gene coding for their resistance.
(These products are for research purpose only.)