Microbial Products

The term industrial microbiology refers to the use of microorganisms for industrial purposes. Such things as anticoagulants, antidepressants, vasodilators, herbicides, insecticides, plant hormones, enzymes, and vitamins have been isolated from microorganisms or produced in large quantities by genetically engineering the organisms with foreign genes.

In commercial industrial plants, microorganisms are widely used to produce numerous organic materials that have far-reaching value and application.

Enzymes. Among the enzymes industrially produced by bacteria are amylases, which break down starches to smaller carbohydrates for commercial use. Amylases are also used in brewing, baking, and textile production. Bacteria have been used to produce proteases, which break down proteins and are used for tenderizing meats, preparing leathers, and making detergents and cheese.

Polysaccharides. The food, petroleum, cosmetic, and pharmaceutical industries use microorganisms to manufacture polysaccharides. For example, the bacteriumXanthomonas campestris, produces a polysaccharide called xanthan, which is used to stabilize and thicken foods and as a base for cosmetics. It is also a binding agent in many pharmaceuticals and is used in textile printing and dyeing. Another polysaccharide of microbial origin is dextran. The bacterium Leuconostoc mesenteroides produces this polysaccharide when it grows on sucrose. Dextran is used to extend blood plasma.

Nutrients. Amino acids, nucleotides, vitamins, and organic acids are produced by the ton by microorganisms. Various types of research and health laboratories use these products, and health-food stores sell them as nutritional supplements. For example, the lysine prescribed by some doctors to treat herpes simplex infections is a product of the bacterium Corynebacterium glutamicumVitamin B12(cyanocobalamine) and vitamin B2 (riboflavin) are produced by a bacterium and a mold, respectively.

Chemotherapeutic agents. Another valuable use of microorganisms in industry is in the production of chemotherapeutic agents. Almost two billion dollars worth of drugs are produced in the United States, mainly by the use of microorganisms. Antibiotics are produced by fungi such as Penicllium and Cephalosporium and by species of the bacterium Streptomyces. Many of these drugs are natural, but several are synthetic or semisynthetic drugs that begin with the naturally occurring molecule, which is then modified.