Activities of microorganisms Industrial Microbiology

Microbes have been used to produce products for thousands of years. Even in ancient times, vinegar was made by filtering alcohol through wood shavings, allowing microbes growing on the surfaces of the wood pieces to convert alcohol to vinegar. Likewise, the production of wine and beer uses another microbe — yeast — to convert sugars to alcohol. Even though people did not know for a long time that microbes were behind these transformations, it did not stop them from making and selling these products.

Both of these are early examples of biotechnology — the use of microbes for economic or industrial purposes. This field advanced considerably with the many developments in microbiology, such as the invention of microscope. Once scientists learned about the genetics of microbes, and how their cells produce proteins, microbes could also be altered to function in many new, and useful, ways. This sparked the application of biotechnology to many industries, such as agriculture, energy and medicine.

Genetic Engineering of Microbes

Genetic information in organisms is stored in their DNA. This molecule holds instructions for how the organism looks and functions. DNA is broken into sections called genes, each of which contains the template for a single protein molecule. Proteins serve as building blocks for the cell, and also carry out other activities. By studying microbes, scientists learned how to cut pieces out of a DNA molecule, and move them to another part. This changes how the cell looks or acts. Scientists can also take genes from one organism and insert them into the DNA of another. This gives the organism entirely new abilities.

This type of genetic engineering — the altering of an organism’s genetic information — has enabled scientists to use microbes as tiny living factories. One example of this is the production of insulin. In humans, the pancreas creates a protein called insulin that regulates glucose — sugar — levels in the blood. People with one type of diabetes cannot produce insulin, so they inject it into their blood throughout the day. To produce cheaper insulin, scientists inserted the human gene for insulin into the DNA of a common intestinal bacterium. This change enabled the bacterium to produce a new product — human insulin.

Food and Agriculture & Microbes

As with the production of vinegar, microbes are used widely in the agricultural and food industries. Bacteria are used in the production of many food products, such as yogurt, many types of cheese and sauerkraut. Farmers also use a bacterium that produces a natural fertilizer. This type of bacterium is normally associated with bean plants, growing in nodules on the roots in a symbiotic — mutually beneficial — relationship. The bacterium converts nitrogen gas in the air to a form that plants can use — like fertilizer. By adding bacteria to the soil, farmers can increase the productivity of the plants.