GENERAL CHARACTERS OF BACTERIA
They are microscopic in nature
The genus bacterium is first established by Eherenberg in 1829
They are omnipresent
Exist as singles or colonies
Present in the form of rods, cocci, or spiral in shape
Absorptive type of nutrition
Some them are spore forming in order to cop up with unfavourable
conditions
Reproduction – Budding, Binary fission, Fragmentation
Transfer of nucleic acid done by conjugation, transformation and
transduction
Some of the cells have capsule, glycocalyx or slime. size – 0.5 to 600 µm
Contains presence pf plasmid
Pili, flagella are present as extracellular appendages
IMPORTANCE OF BACTERIA
Some of the bacteria produces antibiotics, vitamins, enzymes, organic
acids.
Some of them have the ability to fix atmospheric nitrogen and helps in
nitrogen cycles (Nitrobacter, anabene), phosphorous solubilization,
mineral mobilization etc.
Plays a major role in sewage treatment
Probiotics are prepared from bacteria
They help in boosting immunity
Helps in gut immunity
Some bacteria involved in heavy metal , hydrocarbon and pesticide
degradation.( Pseudomonas putida).
Helps in enhancing soil fertility
Helps tp speed up the process of decomposition of paddy husk inorder
to cop up stubble burning
Methanogenic bacteria used for energy production
Some helps in mining process ( Thiobacillus)