Beneficial and harmful bacteria

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Diseases Caused By Bacteria:

Image Showing Diseased Caused by Bacteria.

Name of Bacterium

Diseases Caused

1. Vibrio cholerae

Cholera

2. Salmonella typhi

Typhoid

3. Clostridium tetani

Tetanus

4. Corynebacterium diphtheriae

Diphtheria

5. Mycobacterium tuberculosis

Tuberculosis

6. Mycobacterium leprae

Leprosy

7. Streptococcus pneumoniae

Pneumonia

8. Yersinia pestis

Plague

Beneficial Activities of Bacteria:

Image Showing Beneficial Activies of Bacteria.

Name of bacteriun

Activities

1. Rhizobium

Found in roots of legumes, (Peas, grams,

Pulses etc) fixes atmospheric nitrogen as ammonia, which is then converted into useful amino acid.

2. Azotobacter

Makes the soil fertile. It fixes atmospheric nitrogen in the soil.

3. Streptomycetes

Produces Streptomycin antibiotic.

4. Lactobacillus

Ferments lactose (milk sugar) to lactic acid. This helps in setting of milk into curd.

5. Methanogenic bacteria

Sewage treatment

6. Bifidobacterium

B. longum and B. infantis help prevent diarrhea, candidiasis, and other yeast infections in infants and children.

7. Escherichia coli (E. coli)

Produce vitamin K and biotin which are essential for a variety of cellular processes.

Cyanobacteria

Cyanobacteria are also called as blue green algae are relatively simple, primitive life forms closely related to bacteria. Typically larger than bacteria, they photosynthesize like algae. Cyanobacteria contain a characteristic pigment (phycocyanin) which gives the group their blue-green coloration. Cyanobacteria are also responsible for many of the Harmful Algal Blooms (HABs) that cause ecological, economical and public health concerns in waterways, many times through the production of cyanotoxins.

Differences between Bacteria and Cyanobacteria:

Image Showing Difference Between Bacteria and Cyanobacteria.

Bacteria

Cyanobacteria

Smaller cells

Comparatively larger cells

May have flagella

Do not have flagella

Some bacteria (green) carry out photosynthesis in a different way and do not release oxygen

They all carry out photosynthesis in the usual manner as in green plants and release oxygen

Sexual reproduction by conjugation

Conjugation has not been observed

Reserve food is Glycogen

Reserve food is Cyanophycean starch

Nutrition may be autotrophic or heterotrophic

Nutrition is autotrophic

Spore formation is endogenous

Spore formation is not endogenous

Photosynthetic pigments are bacteriochlorophyll

Photosynthetic pigments is chlorophyll ‘a’

Heterocyst is absent

Heterocyst is present

Composition of cell wall is Glycolipids and peptidoglycan

Composition of cell wall is Cellulose and pectin

Archaebacteria

Kingdom Monera includes two groups; Archaebacteria and Eubacteria. They can only live in areas without oxygen. Main types of Archaebacteria are;

Methanogens: live in oxygen free environments and they produce Methane gasses and found in marshes, lake sediments, and digestive tracts of animals

Thermoacidophilic: Autotrophic producer, live in hot areas and water is a very hot/acidic sulfur spring

Halophilic: live in water with a very high concentration of salt and found in Utah's Great Salt Lake and The Dead Sea in the Middle East.