Microorganisms occupy every small niche of the ecosystem and influence us in many ways. Their influence on human life is generally beneficial but at times can also be detrimental.
The diversified role of microbes begins at their natural habitats. Elements as carbon, nitrogen, oxygen, sulphur, and phosphorus are basic requirement for life forms to survive. They are found in abundance in nature, though not necessarily in forms that organisms can use. Microorganisms mainly bacteria and fungi are primarily responsible for converting these elements into usable forms. Many bacteria and fungi utilize organic molecules releasing carbon dioxide into the atmosphere, which is used by algae, cyanobacteria, and higher plants to produce carbohydrates during photosynthesis. Bacteria also convert atmospheric nitrogen into forms that can be used by plants and animals.
Microorganisms contribute to the production of various food products (bread, cheese, yogurt), beverages (alcohol, wine and beer), medicines as antibiotics (e.g., penicillin, streptomycin, chloramphenicol), vaccines, vitamins, enzymes and many other important products. Microbial products are widely used as aids to nutrition, prevention and treatment of diseases. Many microbial bio-products such as enzymes are used even for improving the quality of life. For example they are used in drain cleaners to remove clogs without adding harmful chemicals to the environment, in detergent formulations and many more.
On one hand when the vast majority of microbes benefit humans, animals, and plants in many ways, many microbial species cause many fatal diseases also, however, fortunately only a minority of all microorganisms are pathogenic. A small group of microbes cause food spoilage, such as soft spots on fruits and vegetables, decomposition of meats, and rancidity of fats and oils.
Microorganisms have been heavily exploited for waste treatment and bioremediation over the last decade. They have been used in sewage treatment, industrial effluent treatment, water recycling, etc. thereby preventing pollution of water bodies. Bioremediation refers to use of microbes to clean up pollutants and toxic wastes produced by various industrial processes, chemical spills, toxic waste sites, oil spills, etc. Microbes have also been used in control of insect pests in agriculture. Use of microbes rather than chemical pesticides prevents the environment from harmful effects of chemical pesticides.
In some cases, microorganisms indigenous to the environment are used; in others, genetically modified microbes are also used. Pseudomonas and Bacillusare the most commonly used bacteria that have been extensively studied and used for different applications
The practical applications of microbiology to produce some common foods and chemicals contribute to biotechnology. Some microorganisms are useful for mankind in their natural forms, while some may be genetically engineered to provide the desired application. The use of recombinant DNA technology has contributed extensively to expand the potential of bacteria, viruses, yeast cells and other fungi as miniature biochemical factories.
Points to remember
- Microorganisms are helpful as well as harmful for other life forms.
- They help to convert essential elements such as carbon and nitrogen to forms that can be utilized by plants and animals
- Microorganisms are widely used in the food products, beverages, medicines as antibiotics, vaccines, vitamins, enzymes, etc.
- Microbial products are widely used as aids to nutrition, prevention and treatment of diseases.