Healthcare

Fungi in Medicine

The kingdom Fungi is a very versatile one.   As we studied early in class, they play several roles in life such as: ecological (parasitic, saprobes, commensals), decomposition, food or food processing, and medicine.   Since earlier times, fungi have been used to produce drugs, like Penicillin, which was discovered during World War II.   Fungi are also used to produce anti-tumor agents such as Ergotamine and its derivates, pigments, and pheromones.   Some of these substances are very important medically, and we have had contact with them at least once in our lives.   Drugs produced by Fungi are synthesized by some species as secondary metabolites. These substances are produced generally during batch cultures.   They are not essential for the producing organism’s growth but they have survival functions in nature, and are used to inhibit other microorganisms. They usually have bizarre chemical structures and possess unusual chemical linkages such as β- lactam rings, which are important in the majority of antibiotics. The β- lactam antibiotics include Penicillin and its derivates, cephalosporins, monobactams and   carbapenems.

The first antibiotic discovered, and the one that revolutionized medicine is Penicillin. It was originally discovered by a bacteriologist named Alexander Flemming in London in 1928.   He was cultivating Staphilococcus aureus in a plate and discovered that the culture had been contaminated by a green mold. He observed that the presence of bacteria near the mold was inhibited.   After that he grew the mold in a pure culture and found that it produced a substance that killed a large number of pathogenic bacteria.   The name of the mold cultivated is Penicillium notatum.   Penicillin is a secondary metabolite of this fungus when its growth is inhibited by stress, using a technique called fed-batch culture in which cells are constantly under stress so they produce a large amount of the desired product.   The production requires control...