Economic Importance of Bacteria: The human relationship with bacteria is quite fascinating. Many bacteria are considered to be hazardous. A specific type of bacteria causes diseases like typhoid, cholera, diphtheria, pneumonia, and numerous infections in open wounds. However, life on Earth would be impossible without the work of some species of bacteria. Certain bacteria are cultivated by humans since they are required for biological processes. Bacteria are one of the most common life forms on the planet. They are also among the tiniest of all living creatures.

The Economic Importance of Bacteria comes from the fact that bacteria may be used by humans in a variety of useful ways. Despite the fact that some bacteria cells play harmful roles, such as causing disease and spoiling food, the economic importance of bacteria includes both their useful and harmful aspects. This article will study more about the Economic Importance of Bacteria and their roles.

What are Bacteria Cells?

Bacteria are the members of a large group of unicellular microorganisms which may have cell walls but lack organelles and an organized nucleus, including some that can cause disease. Bacteria (singular bacterium) are the members of the kingdom Monera, the only prokaryotic kingdom. They comprise a large domain of prokaryotic microorganisms. They may be saprophytes, deriving their food from dead and decaying matter, or parasites, living on or inside the body of other organisms. Some of them also have an autotrophic mode of nutrition. Some forms, like Nostoc, contain chlorophyll.

Fig: Bacteria

Are Bacteria Plants or Animals?

Bacteria are prokaryotic. They do not have a true nucleus and no membrane-bound organelles. Scientists have never entirely agreed on how to classify bacteria. They show heterotrophic nutrition like animals, and some have autotrophic nutrition, like plants. But they cannot be grouped in either of these groups. They are neither plants nor animals.

What is the Economic Importance of Bacteria?

Bacteria have widespread economic importance as they are used in various processes, as discussed below. The Economic Importance of Bacteria examples will help understand the significance of bacteria.

1. Dairy products

Quite a few genera of bacteria are used in food preparation, directly or indirectly.

a. Formation of Curd: Milk is converted into curd by bacterial action. The milk’s lactose is converted into lactic acid, which gives the characteristic sour taste of the curd. Lactic acid bacteria (LAB) like Lactobacillus are added to milk. Indian curd is prepared by inoculating milk with Lactobacillus acidophilus.

b. Yoghurt preparation: It is produced by curdling milk with Streptococcus thermophilus and Lactobacillus bulgaricus.

c. Cheese production starts with milk coagulated with lactic acid bacteria and the curd formed is filtered to separate the whey. The solid mass is then ripened with the growth of mould that develops flavour in it. Propionibacterium shermanii is used to make cheese.

2. In Industry
A large number of products are obtained due to bacterial activity, directly proportional to the economic importance of Bacteria.

Product	Bacteria name
Vinegar or Acetic acid	Acetobacter aceti
Citric acid	Bacillus licheniformis and Corynebacterium species
Vitamin \({B_{12}}\)	Pseudomonas denitrificans
Retting of Fibres like jute, etc.	Clostridium butyricum
The curing and ripening of tea and tobacco leave	Bacillus megaterium
Certain species of bacteria are used in The Preparation of leather from hides and skins of animals.	Species of Staphylococcus, Micrococcus, Corynebacterium, Streptococcus, Enterococcus, Bacillus are used. Besides these, Aerococcus viridans, Pseudomonas Vulgaris, Lactobacillus jensenii are also used.

3. In Medicine
Some bacteria have been exploited to produce antibiotics. Antibiotics like Terramycin, Streptomycin, Tetracycline, Aureomycin, Neomycin are obtained from different bacterial species.

Antibiotic	Bacteria
Chloromycetin	Streptomyces venezuelae
Erythromycin	Streptomyces erythreus
Streptomycin	Streptomyces griseus
Oxytetracycline /Terramycin	Streptomyces aureofaciens
Bacitracin	Bacillus licheniformis
Neomycin	Streptomyces fradiae
Terramycin	Streptomyces rimosus
Aureomycin	Streptomyces aureofaciens

a. Vaccines: Several vaccines have been developed from either killed or attenuated (living but multiplying at low rates) bacteria. For example, tuberculosis vaccine, whooping cough vaccine, plague vaccine, DTP (Diphtheria, Tetanus, Pertussis) vaccine, pneumonia vaccine are all prepared with the help of bacteria.

4. In Maintenance of Environmental Balance and Agriculture: Bacteria act as decomposers. They make the nutrient available for plants. Specific genera of bacteria are used as biocontrol agents in agriculture. Bacillus thuringiensis (Bt) yields protein-based toxins used to kill insects.

5. Nitrogen fixation and soil fertility: Certain bacteria are helpful in the fixation of atmospheric nitrogen. Azotobacter and Clostridium are present in the soil and help in nitrogen fixation. Species of Rhizobium bacteria are present in the root nodules of leguminous plants, and they increase the soil’s nitrogen content by fixing up atmospheric nitrogen. The process is known as symbiotic nitrogen fixation.

Several cyanobacteria also help in nitrogen fixation. Nostoc, Anabaena, etc., possess heterocysts with nitrogenase enzymes and fix atmospheric nitrogen in symbiotic conditions. Nostoc is associated with the coralloid roots of Cycas and helps in this process. Anabaena azollae is associated with water fern, Azolla, and helps in nitrogen fixation in paddy fields.

6. Role in Nitrogen Cycling: Nitrification is one of the most critical steps in the nitrogen cycle, performed by nitrifying bacteria. Nitrifying bacteria are chemolithotrophic organisms that include the genera Nitrosomonas, Nitrococcus, Nitrobacter, Nitrobacillus, etc. These bacteria get their energy by the oxidation of inorganic nitrogen compounds.

The denitrifying bacteria, like Pseudomonas denitrificans, Thiobacillus denitrificans, transform the nitrates to atmospheric nitrogen.

7. Biogas Production: Biogas is a standard domestic and industrial fuel, which contains \(50-60\%\) methane, \(30-40\%\) carbon dioxide, \(0-3\%\) Sulphur compounds, and traces of other gases like hydrogen CO, nitrogen, etc.

1. In a biogas digester, cattle dung is used to obtain gas (gobar gas) in the following steps:

a. Hydrolysis is the initial step that needs anaerobic bacteria like Clostridium, Pseudomonas, etc.
b. Acidogenesis is the second step, in which the facultatively anaerobic, acidogenic bacteria and obligate anaerobic organisms help convert the simple organic material into acids like formic acid, acetic acid, etc.
c. Methanogenesis is the last step, in which anaerobic Methanogenic bacteria like Methanobacterium, Methanococcus, etc., convert organic acids into Methane.

8. Sewage Treatment: Sewage is agricultural and domestic waste products that pollute the water. The treatment to remove such waste is partially chemical, biological treatment.
a. Secondary treatment is the biological treatment, which reduces the BOD significantly. Aerobic bacteria are used in this process.
b. Tertiary treatment is done once there is a reduction of BOD in the settling tank. Mainly Methanogens grow anaerobically and produce biogas.

Formation of Curd with Bacteria

Curd formation from milk is performed by mixing LAB (Lactic Acid Bacteria), like Lactobacillus, with warm milk. These bacteria convert the milk sugar (lactose) into lactic acid resulting in the formation of curd.
Once the curd is made, it is transferred to a cooler place to reduce the further growth of bacteria. Otherwise, the bacteria would make it sour by excessive production of lactic acid.

Check Details on Kingdom Monera Here

How are Bacteria Harmful to us?

1. Spoilage of Foodstuff: Cooked food, fruits, vegetables, butter, fish and meat are spoiled by bacteria, particularly during summer months, by causing putrefaction of food materials.

Fig: Food Poisoning Bacteria

Certain bacteria like Salmonella typhimurium and Clostridium botulinum cause a severe type of food poisoning when bacteria-contaminated food is consumed. Clostridium botulinum causes food poisoning, commonly known as botulism.
2. Reduction of Soil Fertility – Denitrification: Certain species of anaerobic bacteria inhabit soils that are either waterlogged or have high organic matter content. These bacteria reduce soil fertility by depleting the soil’s nitrogen content. They break down nitrates present in the soil and release nitrogen, which escapes into the air, thereby reducing soil fertility (denitrification).
3. Animal Diseases: Bacteria cause tuberculosis in cattle, anthrax in sheep, cholera in chickens and pneumonia in horses, sheep and goats.
4. Human Diseases: Many serious diseases are caused by bacteria in human beings. Some of these are as follows:

Disease	Bacterium
Cholera	Vibrio cholerae
Diphtheria	Corynebacterium diphtheriae
Diarrhoea	Bacillus coli
Leprosy	Mycobacterium leprae
Plague	Pasteurella pestis
Tetanus	Clostridium tetani
Tuberculosis	Mycobacterium tuberculosis
Pneumonia	Streptococcus pneumoniae
Typhoid	Salmonella typhi

5. Plant Diseases: Several plant diseases are induced by bacteria. They cause leaf spots, soft rots, vascular diseases, and bacterial galls. Xanthomonas citri causes citrus canker.
6. Bioweapons: A bioweapon or biological weapon is a device that carries and delivers a disease-causing biological agent (like bacteria, viruses, genetically altered organisms) or a toxin derived from it to the target organism. The biological agent or toxin is called a bioweapon agent. Biological agents are used against humans, crops and animals. Such use of bioweapons is termed BioWare or biological war. Some of the bioweapons can cause anthrax, smallpox, plague and gastroenteritis. Bacillus anthracis is the causative agent of anthrax, Vibrio cholera of gastroenteritis and Yersinia pestis of plague. Botulinum toxin from Clostridium botulinum is used to cause fatal food poisoning. Some of these agents have already been used. For example, anthrax bacterium was sent through letters in \(2001.\) Bioweapons are low-cost weapons and cause far more casualties than conventional weapons.

Summary

In this article, we studied that bacteria are the members of the kingdom Monera. They are the most diverse organisms with wide distribution, modes of nutrition, reproduction, etc. They are saprobiotic, parasitis, and autotrophic in their nutrition. Some forms are helpful for human beings, while most others are pathogenic and cause harm to animals and plants. We also looked at the economic importance of bacteria processes through some examples.

FAQs

Q.1. What is Koch’s postulate on bacteria?
Ans: The bacteria must be present in every case of the disease. The bacteria must be isolated from the host with the disease and grown in pure culture. The specific disease must be reproduced when a pure culture of the bacteria is inoculated into a healthy susceptible host.

Q.2. What are the three important uses of bacteria?
Ans: Bacteria are used in Biogas production, Cheese production, improving soil’s health and productivity, and sewage treatment.

Q.3. Which bacteria are responsible for the formation of curd from milk?
Ans: Lactobacillus species bacteria are responsible for the formation of curd from milk.

Q.4. What is the major function of an Economic Importance of Bacteria?
Ans: Some of the primary functions of the economic importance of Bacteria are Curing of Cheese, In Maintenance of Environmental Balance and Agriculture, Nitrogen fixation and soil fertility,  In Medicine, Sewage treatment, Biogas production, etc.

Q.5. Which bacteria are responsible for causing Leprosy disease in human beings?
Ans: Mycobacterium leprae bacteria are responsible for causing Leprosy disease in human beings.

Q.6. List a few harmful roles of bacteria.
Ans: Spoilage of Foodstuffs, Reduction of Soil fertility Denitrification, Animal Diseases, Human Diseases, Plant Diseases, etc., are a few harmful roles of bacteria.