The economic importance of bacteria includes the production of traditional foods (such as curd or yogurt, cheese, ghee, and vinegar), vitamins, dietary supplements, medicines, nitrogen cycles, bioweapons.
Bacteria are also important in agriculture because they help in composting and producing fertilizer by natural means.
Bacteria are used in genetic engineering where specific genes are introduced into bacteria for the production of desired products.
Economic importance contains both useful and harmful activities related to the topic, here we will discuss the benefits and harm caused by bacteria.
Beneficial Activities of Bacteria
Industrial uses of bacteria in
- Biotechnology – It’s a technology that involves the biological systems, living organisms, or parts of this to develop or create different products. For example, the use of microorganisms including bacteria in the manufacturing industries. The chemical manufacturing of acetone, enzymes, alcohol (ethanol), organic acids, and perfumes are carried out through this process.
- Making dietary supplements and pharmaceuticals – Some vitamins are used as external food supplements. E. coli bacteria are used to produce D-amino acids such as D-p-hydroxyphenylglycine, which is an important intermediate for the synthesis of the antibiotic amoxicillin.
- Pest control – Some bacteria can be used in place of pesticides under biological pest control. This process commonly uses Bacillus thuringiensis (Bt.) and soil-dwelling bacterium.
- Acetobacter aceti is used to make vinegar (Acetic acid) – In this process, ethanol is converted into acetic acid (CH3COOH).
- Production of vitamins:
- Clostridium butylicum is used in the commercial preparation of Riboflavin (vitamin B12) and Butyric acid
- E. coli (Escherichia coli) or coliform bacteria produces vitamin E, vitamin K, etc.
- E. coli bacteria are present in human and other herbivores’ intestines which helps the body in digesting the food we eat and produces vitamin B1, B2, and K. Bacteria living in the gut are called gut microbiota in cattle, horses, and other herbivores, for example, Ruminococcus spp., helps in the digestion of cellulose by secreting the enzyme cellulase. This is how herbivores are able to fulfill the body’s energy demand they need from grass and other plants.
- Bacillus and Propionibacterium produces vitamin B12.
- Retting of fibers – Separation of fibers from plants with the help of bacteria.
- Bioremediation – Bioremediation bacteria are used to remove pollutants from contaminated water, soil, and other materials. For example;
- In Ganga river water bacteria named Bdellovibrio bacteriovorus and Bacteriophage are present where they kill the other polluting bacteria and make the water fit.
- In degrading oil in seawater, in it, a bacteria named Alcanivorax borkumensis used to remove oil from the water surface.
- Pollution indicator – Water in which E. coli bacteria are present is called polluted water and is an indicator of fecal contamination in water. The quality of water depends on the number of E. coli. If E. coli are very much in number, the water will be highly polluted. So, E. coli is known as a pollution indicator.
- Genetic engineering – Genetic engineering is also called genetic modification or genetic manipulation. In this process, direct manipulation of an organism’s genes is done using biotechnology. Mainly E. coli and Agrobacterium bacteria are used in genetic engineering.
- Curing or flavoring of tea and processing of tobacco leaves – For this process Bacillus megatherium and Micrococcus condiscence are used.
What is an antibiotic?
Anti means against and biotic means life so any substances which are against the life of an organism are called antibiotics. Some substances produced by microorganisms that inhibit the growth of other microorganisms are called antibiotic substances. Many antibiotic medicines are obtained from bacteria.
1st antibiotic used in the 2nd world war by American soldiers is Streptomycin which is obtained from Streptomyces griseus (It is an actinomycete).
- Streptomyces venezuelae – Chloramphenicol (Chloromycetin)
- Streptomyces rimosus – Terramycin
- Streptomyces fradiae – Neomycin
- Streptomyces aureofaciens – Aureomycin
- Bacillus polymyxa – Polymyxin
- Bacillus subtilis – Antibiotics produced are three ribosomal antibiotics (TasA, Subtilosin, and Sublancin), four nonribosomal antibiotics (Bacitracin, Bacilysin, Plipastatin, and Surfactin), Bacilysocin, and Neotrehalosadiamine (NTD)
- Streptomyces strains – Tetracycline
Foods products made from lactic acid bacterial species are Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Weissella in which species of lactobacillus bacteria are more commonly used in the fermentation of dairy products are:
- Streptococcus lactis
- Lactobacillus lactis
Lactobacillus lactis increases vitamin B12 in curd, Lactic Acid Bacteria (LAB) also helps in the disease-causing microbes in the stomach.
Nitrogen Fixation or diazotrophy
Nitrogen fixation (N2 → NH3) is both biological as well as a chemical process through which covalent bonded atmospheric nitrogen (N2), is converted into ammonia (NH3) or any nitrogenous compounds like amino acids, nitrate, and ammonium salts. Where nitrogen has a nonzero oxidation state, this is done typically in soil or aquatic systems and also artificially in industry.
Nitrogen fixation is done by two processes:
- Symbiotically: In this process, bacteria live symbiotically within the plant body and do nitrogen fixation.
- Azorhizobium – In the stem nodules of Sesbania
- Azospirillium – Found on the root surface of cereals that is, superficial symbiosis. For example Rice, Maize, Wheat
- Frankia – In the root nodules of non-legumes. For example Casuarina, Alnus
- Rhizobium – In the root nodules of legumes
- Asymbiotically: Some bacteria are found freely in soil and do nitrogen fixation.
The process of formation of ammonia is called ammonification. Ammonifying bacteria help in the process of ammonification (Protein → NH3). It is a biological process, these bacteria convert protein (present in decaying plants and animals) into ammonia (NH3).
- Bacillus Vulgaris
- Bacillus Romosus
- Bacillus Mycoids
Nitrification is done by nitrifying bacteria which are chemoautotrophs, in which bacteria convert ammonia (NH3) into nitrite (NO2–) and further nitrate (NO3–) and it is a biological process.
- Nitrosomonas (2NH3 + 3O2 → 2NO2– + 2H+ + 2H2O + Energy)
- Nitrococcus (2NH3 + 3O2 → 2NO2– + 2H+ + 2H2O + Energy)
- Nitrobacter (2NO2 + O2 → 2NO3– + Energy)
- Nitrocystis (2NO2 + O2 → 2NO3– + Energy)
Harmful Activities of Bacteria
Diseases caused by bacteria in human beings
|Tuberculosis (T.B)||Mycobacterium tuberculosis|
Disease caused by bacteria in animals
Disease caused by bacteria in plants
|Bacterial leaf blight of rice||Xanthomonas oryzae|
|Blackleg and soft rot of potato||Erwinia carotovora atroseptica|
|Black rot of crucifers||Xanthomonas campestris pv. campestris (Xcc)|
|Citrus canker||Xanthomonas citri|
|Crown gall in many plants||Agrobacterium tumefaciens|
Denitrifying bacteria helps in the process of denitrification (NO3- → N2) which is both a biological as well as abiological process, in which some bacteria convert soil nitrates (NO3–) into nitrites (NO2–) and then nitrogen (N2) this process is called denitrification. These bacteria reduce the fertility of the soil.
- Thiobacillus denitrificans
- Pseudomonas denitrificans
- Micrococcus denitrificans
Food poisoning or Foodborne illness
Botulism is caused by Clostridium botulinum and sometimes Clostridium butyricum and Clostridium baratii – It is an obligate anaerobe. It can not survive in our body because of the presence of oxygen (aerobic environment). It is a rare and the most lethal type of food poisoning.
These bacteria only survive in absence of oxygen. These bacteria multiply in canned food. Their toxins attack the parasympathetic nervous system, which leads to paralysis of both smooth and striped muscles that results in difficulty in breathing which causes asphyxia and leads to immediate death.
Some bacteria are used as bioweapons such as:
- Bacillus anthracis (rod-shaped, gram-positive bacteria)— Causes Anthrax, a serious infectious disease. It can be found naturally in soil and commonly affects domestic and wild animals all around the world.
- Clostridium botulinum, Clostridium butyricum, Clostridium baratii— Causing food poisoning.
- Vibrio cholerae— Causes Cholera by infecting the intestine. It is an acute diarrheal illness in which people can get sick when they take food or water contaminated by cholera bacteria. The infection is often mild or without symptoms, but can sometimes be severe and becomes life-threatening.
Several bacterial forms cause water pollution. These bacteria spoil the water and make it unfit for living organisms.
- Salmonella typhi
- Vibrio Cholerae