Python Notes for mca i year students osmania university.docx
Economic Importance of Microbes
1. ECONOMIC IMPORTANCE OF MICROBES
Dr. K. M. Ranjalkar
Assistant Professor & Head
Department of Botany,
Late Pushpadevi Patil Arts and Science College, Risod,
District Washim (M.S.) India.
E-mail: botanyhodlppc@gmail.com
Cell +91 9398711627
2. What is microbes ?
Microbes or Microorganisms are minute living things that are
not usually unable to be viewed with naked eye.
Microorganisms includes-
-Viruses
-Bacteria
-Protozoa
-Microscopic Fungi
-Microscopic Algae
3. Viruses
Definition of Viruses: The definition of viruses has been given by various
scientist. Viruses have been defined as “the smallest units showing
reproductive property considered typical of life”
S. E. Luria (1953) defined viruses “sub-microscopic entities capable of
being introduced into specific living cells and of reproducing inside the
such cells only”
F. C. Bowden (1964) defined viruses as “Viruses are sub-microscopic,
infective entities that multiply only intracellularly and are potentially
pathogenic”
4. PLANT VIRUSES
Viruses are parasite on host cells of plant and affect the metabolic activities.
Thus they develop several diseases in Plants, some described below-
1. Tobacco Mosaic Virus (TMV)
2. Turnip Yellow Mosaic Virus (TYMV)
3. Potato Virus X (PVX) and Potato Virus Y (PVY)
4. Cauliflower Mosaic Virus (CaMV)
5. Beet Yellow Virus (BYV)
6. Rice Dwarf Virus (RDV)
5. Economic Importance
1. There are about 1000 viruses which attack on animal and plants causes
diseases in them.
2. Some common viral diseases of plant are Tobacco mosaic, Potato leaf roll,
Bunchy top of banana, Yellow vein mosaic of bhindi etc.
3. Some very common viral diseases of mammals are influenza, small pox,
mumps, measles, yellow fever, AIDS etc.
4. Viruses which infect the bacteria are known as bacterial virus or
bacteriophage or phage. Therefore they are employed in the biological
control of diseases caused by bacteria e.g. Cholera, dysentery and plague
etc.
5. The phages may be harmful to antibiotic synthesis by bacteria. Therefore,
precautions should be taken during antibiotic synthesis of bacteria.
6. 6. The water may be polluted by some bacteria and blue green algae. For the
purification of this water, Bacteriophage and Cyanophage can be used
as they will kill harmful bacteria and blue green algae, respectively and
thus they acts as scavengers by feeding on bacteria.
7. Some plant pathogenic or otherwise harmful bacteria may be present in soil
microflora. The use of bacteriophage can kill these harmful form and soil
Fertility can be increased.
8. Phages can transfer the genetic material of one bacterium to the other by the
process of transduction. This process can be use in the transfer of useful
genes of one bacterium to the other.
7. Bacteria
• Some bacteria are directly or indirectly beneficial to man. Thus, these may be considered both
as “friends and foes” to man.
• USEFUL BACTERIA
1. Decomposition: Several Sporophytic bacteria acts as scavenger of nature by decomposing
the dead bodies of animal and plant debris.
e.g.Clostridium thermocellum, Thermoactinomyces, Bacillus sterothermophilis etc. play an
important role in decomposition of the dead organic matter.
2. Sewage Disposal: Microorganism convert sewage from organic to inorganic state by a process
is called as mineralization or stabilization.
e.g. Actinobacter, Flavobacterium, Hyphomicrobium, Pseudomonas.
3. Agriculture: Some bacteria are useful in increasing soil fertility.
Saprophytic ammonifying bacteria convert the proteins, amino acid and nucleic acid of
dead bodies into ammonia.
Nitrification- by Nitrosomonas and Nitrobacter.
Symbiotic Bacteria- Rhyzobium, Azatobacter, Azospirilum, Clostridium (anaerobic)
Photosynthetic Bacteria: Rhodospirillum, Rhodomicrobium and Chlorobacterium.
8. 4. Industrial Uses: In Industry, many bacteria are employed in a number of processes
such as retting, tanning and fermentation.
Chemicals produced by bacteria-
Industrial Chemicals Bacterium Employed
Acetic Acid Acetobacter acetii
Gluconic Acid Acetobacter
Lactic Acid Lactobacillus delbruckii
Propionic Acid Propionibacterium propionum
Citric Acid & Protease Bacillus licheniformis
Lysine Brevibacterium flavum
Glutamic Acid Corynebacterium glutamicum
Amylases Bacillus diastictus
Acetone Clostridium acetobutylicum
Butanol Clostridium saccharo-acetobutylicum
Glycerol Bacillus subtilis
Ethanaol Thermoanerobacter ethanolicus
Methane Methanobacillus
9. 5. Antibiotics: Antibiotics are substances produced by microorganism
which inhibits or kill other microorganism.
Antibiotics produced by bacteria-
Name of Antibiotics Bacterium /Source
Bacitracin Bacillus licheniformis
Gramicidin & Tyrothrycin B. brevis
Polymixin-B B. polymyxa
Streptomycin & Actinide Streptomyces griseus
Cholomyphenicol S. venezuelae
Tetracycline S. auryfaciens
Erythromycin S. erythreus
Neomycin S. fradiae
Amphotericine-B S. nodosus
Amphomycine S. canas
Oxytetracycline S. rimosus
Kanamycin S. kanamyceticus
10. 6. Biotechnology: With the help of recombinant DNA technology, insulin and
interferon's are commercially produced using the strains of Escherichia coli. Insulin
is used to control diabetics. Interferon's play an important role in controlling cancer.
7. Genetic engineering: Agrobacterium tumefactions is used as vector in genetic
engineering.
8. Bacterial pesticides: Many pest of vegetable crops are suppressed by the toxic action
of Bacillus thuringensis. Mosquito larva can be destroyed by Bacillus sp.
9. Biodegradation of insecticides and herbicides: Bacteria are useful in the
biodegradation of the pesticides e.g. 2, 4-D is decomposed by Achromobacter and
Coryne bacterium. Paraquants the weed killer degraded by Coryne bacterium and
Clostridium.
11. HARMFULL ASPECTS
1) Spoilage of food material: Several saprophytic bacteria grows on food material
such as cooked food, mutton, fish, eggs, milk, milk products, vegetables, fruits,
beverages, pickles etc. and decay the food material.
The bacteria secretes chemical substance cause food poisoning e.g. Achromobacter,
Pseudomonas, Escherichia, Proteus, Flavobacterium, Micrococcus, Clostridium,
Salmonella and Staphylococcus.
Botulism-A food poisoning caused by the toxins produced by Clostridium botulinum
releasing the very toxic substance ‘botulin’ which causes botulism.
2) Reduction of Soil Fertility: Some anaerobic soil bacteria such as Bacillus
dentrification, Pseudomonas denitrifican and Thiobacillus denitrificans are
abundant in water lodge soil. They reduce soil nitrates so that free nitrogen escapes
into the environment. Such bacteria are called as denitrifying bacteria.
3) Animal diseases: Bacteria causes diseases of domestic animals like tuberculosis of
cattle, pneumonia, septicemiain cattle, gladder in sheep, horse and goats.
12. Some Important animal diseases caused by bacteria
Diseases of Animals Bacterium
Anthrax Bacillus anthacis
Actinomycosis of Cattle Mycobacterium bovis
Brucellosis of domestic animals
(Cow, horses, goats etc.)
Brucella abortus
Listeriosis of calf, sheep and
chicken
Monocotygenes spp.
Tuberculosis of dogs, cattle etc Mycobacterium tuberculosis
Vibriosis Vibrio tetus
Black legs of cattle Clostridium chanvei
Gladers disease in donkey and
horses
Actinobacillus spp.
Actinomycosis of cattle Actinomycosis bovis
13. Human diseases Bacteruium
Typhoid Salmonella typhii
Pneumonia Streptococcus pneumonia
Gastero enteritis Salmonella, Escherichia coli
Dysentry Bacillus dysenteriae
Cholera Vibrio cholera
Plague Pasturella pestis
Tetanus Clostridium tetani
Botulism Clostridium botulinum
Diptheria Corynebacterium diptheriae
Tuberculosis Mycobacterium tuberculosis
4. Human Diseases: Certain bacteria attack digestive, circulatory and
respiratory systems and causes diseases.
Some Important Human diseases caused by bacteria
15. 5) Plant Diseases: Bacteria causes several diseases in economically important
plants.
Some Important Plant diseases caused by bacteria
Plant disease Pathogen
Bacterial blight of paddy Xanthomonas oryzae
Black chaff of wheat Xanthomonas transluscens
Red stripe of sugarcane Pseudomonas rubri lineans
Soft rot of potato, mango & carrot Erwinia carotovora
Canker of tomato Corynebacterium michiganesse
Fire blight of apple and pear Erwinia amylovora
Crown gall of apple and pear Agrobacterium tumefaciens
Black knot of grapescane Pseudomonas tumefaciens
Citrus canker Xanthomonas citri
Gummosis of sugarcane Xanthomonas vasculorum
Angular leaf spot of cotton Xanthomonas malvacearum
16. 6) Water pollution: The bacteria like Shiegella dysenteriae, Vibrio cholerae
and Salmonella typhi polluted drinking water.
Spot of peach Xanthomonas pruni
Scab of potato Streptomyces scabies
Black rot of cabbage X. campestris
Blight of beans Pseudomonas phaseolicala
Tendu of wheat Corynebacterium tritici
Wilting of cucurbits Erwinia spp.
