Topic :
General characteristics of
extremophiles
presented by :Gaurav Kumar pal
M.Sc. Applied microbiology
Contents :EXTREMOPHILES
1.Thermophiles
2.Psychrophiles
3.Osmophiles
4. Methanogens
5. METHYLOTROPHS
6. Alkaliphiles
7. Acidophiles
8. Halophiles
9. Reference
EXTREMOPHILES :Having optimal condition outside the normal
environment.
 These organism are not only survive in extreme
or unusual enviroment on the earth but also
reproduced & grow.
 Mostly extremophiles are ARCHAEA.
 They are used in BIOTECHNOLOGY &VARIOUS
INDUSTRIES

Thermophiles – Heat Loving
THERMOPHILES
 CHARACTERISTICS

:-
"Thermopiles" are heat loving microorganisms which can
grow in the temperature 55-65 °C
minimum growth temperature:- 45°C

optimal growth temprature:-55- 65°C
 Maximum growth temperature:- 110 °C

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They contain heat-stable enzymes.
Used in biotechnology & medicine.
Example:- Thermos aquatics and Thermococcus littorals are
used as sources of the enzyme DNA polymerase, for the PCR
technique in DNA fingerprinting.
PSYCHROPHILES - Cold Loving
PSYCHROPHILES :CHARACTERISTICS
Most
:-
psychrophiles are bacteria or archaea.
Psychrophiles are also called as Cryophiles .
found in Arctic and Antarctic oceans & deep ocean.
They are capable of growth and reproduction in cold temperatures,
ranging from 4°C to +15°C.
They having the cold –active enzyme.
Having special proteins or cryoprotectants called antifreeze proteins.
Examples are Arthrobacter sp., psychrobacter sp., and members of
the genera Halomonas, Pseudomonas, Hyphomonas, and
Sphingomonas .
Used Psychrophilic bacteria Rhodococcus sp. in biodegradation.
Also used in pharma, baking , & fermentation industry .
OSMOPHILES :SUGAR LOVING ORGANISM
OSMOPHILES
Osmophillic organisms are extremophiles that
are able to grow in high sugar concentration .
 osmophiles protect themselves against this high
osmotic pressure by the help of osmoprotectants
such as alcohols and amino acids .
 Osmophile are important because they cause
spoilage in the sugar and sweet goods industry.
 Example of osmophiles is Aspergillus,
Saccharomyces, Enterobacter aerogenes and
Micrococcus.

Methanogens :Methane producing organism
METHANOGENS :Methanogens belong to the Archaea group of the
Prokaryotes.
 Methanogens are bacteria that produce methane
gas.
 Methanogens require anaerobic conditions.
 Many require warm conditions to work best.
 Methanogens are chemoautotrophs.
 They can be used as sources of biogas gas.
 This would be a renewable source of energy.

Using acetate that may be derived from the
decomposition of cellulose:
CH3COO+ + H-  CH4 + CO2 +36 kJ mol-1
OR
 Using hydrogen and carbon dioxide produced by
the decomposers:
4 H2 + CO2  CH4 + 2 H2O
+130.4 kJ mol-1


Examples:-

Methanobacterium formicum

Methanococcus deltae
METHYLOTROPHS:METHANE DEGRADING ORGANISM
METHYLOTROPHS:They
are aerobic organism .
are microorganisms that can use to reduced one
carbon compounds, such as methanol or methane.
The used carbon source for their growth.
 may grow on other organic molecules including
Organic acids Ethanol And sugars .
can degrade the methane, and called
methanotrophs.
Methylococcus capsulatus is used to degrade
methane and other pollutants .
Example:
Methylosinus sp.& Methylococcus capsulatus
Alkalophiles:-
Alkalophiles:

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They grow at the Ph 9 and above.
isolated from alkaline environments.
cell surface play a key role in keeping the
intracellular pH value in the range between 7
and 8.5 .
Used:Biological detergents.
Enzyme production.
Example :- bacillus okhensis
,alkalibacterium iburiense
Acidophiles:acid loving organism

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They grow at pH 3 or
below .
these organisms have the
ability to pump hydrogen
ions out of their cells .
The internal ph of the cell
is about 6.5 & external ph
is about 2.5 or less
Used:- Enzyme
production.
Example:-sulfolobus
,picrophilus
,ferroplasma
Halophiles
Halophiles:salt loving organism

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are organisms that live in high salt concentrations.
halophile means “salt loving”.
most halophiles are aerobic and heterotrophic.
some are anaerobic and photosynthetic.
They are pinkish in colour.
Having carotenoids for ultraviolet protection.
Example :- halobacterium , halococcus
Reference
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Prescott & harley ,klein (2002) ,Microbiology second edition
,Arehaeobacteria, wm.C.brown publishers(497-504).
Tortora J.G., Funke R.b. ,Christine l. case,
(1997),microbiology an introduction sixth edition ,microbial
growth ,Addison wesley longman (154-158).
ALCAMO I. EDWARD(2001), Fundamentals of microbiology
fifth edition ,bacterial structure and growth ,jones and
bartlett publishers (112-115,122 ).
Wistreich A.G.,MAX. D.lechtman(1988) Microbiology fifth
edition ,microbial ecology and environmental activities,
Collier macmillan publishers LANDON(406-408).
http://en.wikipedia.org/wiki/Extremophile.
http://www.daviddarling.info/encyclopedia/H/halophile.html
THANKS