Extremophilic organisms are organisms that can survive exremities that are detrimental for other forms of life. Here is a presentation that discuss such microorganisms in detail
Halophiles (Introduction, Adaptations, Applications)Jamil Ahmad
Introduction
Halophiles are organisms that thrive in high salt concentrations.
They are a type of extremophile organisms. The name comes from the Greek word for "salt-loving".
While most halophiles are classified into the Archaea domain, there are also bacterial halophiles and some eukaryota, such as the alga Dunaliella salina or fungus Wallemia ichthyophaga
Halophiles (Introduction, Adaptations, Applications)Jamil Ahmad
Introduction
Halophiles are organisms that thrive in high salt concentrations.
They are a type of extremophile organisms. The name comes from the Greek word for "salt-loving".
While most halophiles are classified into the Archaea domain, there are also bacterial halophiles and some eukaryota, such as the alga Dunaliella salina or fungus Wallemia ichthyophaga
Microbial interactions are ubiquitous, diverse, critically important in the function of any biological community.
The most common cooperative interactions seen in microbial systems are mutually beneficial. The interactions between the two populations are classified according to whether both populations and one of them benefit from the associations, or one or both populations are negatively affected.
Microbial interactions are ubiquitous, diverse, critically important in the function of any biological community.
The most common cooperative interactions seen in microbial systems are mutually beneficial. The interactions between the two populations are classified according to whether both populations and one of them benefit from the associations, or one or both populations are negatively affected.
Biodiversity, Microbial Biodiversity, Bacterial Biodiveristy, Archae Biodiversity, Protozoa Biodiversity, Fungal Biodiversity, Origin of Life, Origin of Life on Earth, Chemical Evolution, Physical Evolution, Biological Evolution
The archaebacteria
group members
Rameen nadeem
Syeda iqra hussain
Hina zamir
Mahnoor khan
Maleeha inayat
Background
Biologists have long organized living things into large groups called kingdoms.
There are six of them:
Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
Some recent findings…
In 1996, scientists decided to split Monera into two groups of bacteria:
Archaebacteria and Eubacteria
Because these two groups of bacteria were different in many ways scientists created a new level of classification called a DOMAIN.
Now we have 3 domains
Bacteria
Archaea
Eukarya
KingdomArchaebacteria
Any of a large group of primitive bacteria having unusual cell walls, membrane lipids, ribosomes, and RNA sequences, and having the ability to produce methane and to live in anaerobic, extremely hot, salty, or acidic conditions
The Domain Archaea
“ancient” bacteria
Some of the first archaebacteria were discovered in Yellowstone National Park’s hot springs
Prokaryotes are structurally simple, but biochemically complex
Basic Facts
They live in extreme environments (like hot springs or salty lakes) and normal environments (like soil and ocean water).
All are unicellular (each individual is only one cell).
No peptidoglycan in their cell wall.
Some have a flagella that aids in their locomotion.
Most don’t need oxygen to survive
They can produce ATP (energy) from sunlight
They can survive enormous temperature extremes
They can survive under rocks and in ocean floor vents deep below the ocean’s surface
They can tolerate huge pressure differences
STRUCTURE
Size
Archaea are slightly less than 1 micron long.
A micron is 1/1,000 of a millimeter.
In order to see their cellular features, scientists use powerful electron microscopes.
Shape
Shapes can be spherical or ball shaped and are called coccus.
Others are rod shaped, long and thin, and labeled bacillus.
Variations of cells have been discovered in square and triangular shapes.
STRUCTURE
Locomotion
Some archaea have flagella, hair-like structures that assist in movement.
There can be one or many attached to the cell's outer membrane. Protein networks can also be found on the cell membrane, which allow cells to attach themselves in groups.
Cell Features
Within the cell membrane, the archaea cell contains cytoplasm and DNA, which are in single-looped forms called plasmids.
Most archaeal cells also have a semi-rigid cell wall that helps it to maintain its shape and chemical balance.
This protects the cytoplasm, which is the semi-liquid gel that fills the cell and enables the various parts to function.
STRUCTURE
Phospholipids
The molecules that make up cell membranes are called phospholipids, which act as building blocks for the cell.
In archaea, these molecules are made of glycerol-ether lipids.
Ether Bonding
The ether bonding makes it possible for archaea to survive in environments that are extremely acidic or al
Extremophile Current Challenges and New Gate of Knowledge by Nanoparticles Pa...IOSRJPBS
Extremophiles are a unique organisms that have ability to exist in critical environmental conditionssuch as temperatures, pH, saline and pressures.They are characterized by high efficiencies in growth and enzymes product that led them to be a candidate in industrial productions as detergents, brewing, cosmetics, dairy products, bakery, textiles, and as degradation materials.. More information concerning the behavior of extremophiles is still required. Recently, several studies are conducted to detectdeep information about extremophiles using the advantages of nanoparticles. For instances, gold (Au) and silver (Ag) nanoparticles open a new gate of knowledge for researcher particularly for study different pathways of extremophiles. In this review we first concerns with extremophiles definition, history and applications then we reflects general idea about the environmental conditions taking in account the uses of nanoparticles.
The word Archae came from the Greek word Arkhaion, which means “Ancient”.
Archae is also the Latin name for Prokaryotic Cells. Archaea that growing the hot water of the Hot Spring in Yellowstone National Park produce a bright yellow color.
Archaebacteria are known to be the oldest living organisms on earth. They belong to the kingdom Monera and are classified as bacteria because they resemble bacteria when observed under a microscope. Apart from this, they are completely distinct from prokaryotes. However, they share slightly common characteristics with the eukaryotes.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
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A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
2. EXTREMOPHILES
Organisms found living in extreme harsh environments.
Word originated from Greek- Extremus + Philia which
means extreme loving.
Most members of this group comes under the domain
Archae.
These include thermophiles, hyperthermophiles,
thermoacidophiles, alkaliphiles, psychrophiles,
halophiles, barophiles, radiation resistant bacteria
and endoliths.
3. DEFINITION
Organisms lives in physically/geochemically extreme
conditions that are mostly detrimental for other forms of
life.
In other words, an extremophile is a
microorganism, mostly an Achaeon that lives in
conditions of extreme acidity, alkalinity, temperature,
salinity, pressure, nutrient scarcities etc.
4. HOW DO THEY LIVE SO?
Extremozymes- specialized enzymes that
are highly stable.
Can tolerate extremes of temperature, pH,
salinity that would inactivate other
enzymes.
Important in industries because of this
property.
7. TYPES
Psychrophiles
Temperatue range is -15 to 150
C
Also known as cryophiles.
Have an optimum temperature of 150
C or lower
Isolated from Arctic and Antarctic habitats (90% of the
ocean is 50
C or colder)
Also found in ice bergs, glaciers, snowfields etc
Metabolism is quite normal at colder temperatures.
Cell membranes-high levels of fatty acids which remain
fluid at colder temperatures.
Proteinaceous antifreeze mechanism to protect the cell
and DNA
Some of them cause spoilage in refrigerated food materials.
Eg: Arthrobacter spp, Psychrobacter spp, Halomonas
spp, Pseudomonas, sphingomonas
8. FIRMICUTES
Gram positive, spore forming bacterial family that
can survive desiccation and can survive extreme
conditions.
This group also is an example for extremophilic
true bacteria (eubacteria).
Plays an important role in the spoilage of beer, wine
and cider.
Eg: Helicobacterium spp, Mycoplasma,
Clostridium spp.
9. Many members of the Family Firmicutes are also
thermophiles.
Eg: Bacillus stearothermophilus
Recently, a DNA polymerase derived from these
bacteria, Bst polymerase has become important in
biotechnology.
Bst polymerase- helicase like activity (making it
able to unwind DNA strands.
Optimum functional temperature is 60-650
C and get
inactivated at temperatures above 800C
10. THERMOPHILES
Greek- thermotita (heat) and philia (love)
Temperature loving organisms.
Most members are Archae
Grows in a temperature range of 55-1130C
Mostly found in geothermally heated regions on earth
viz., hot springs, hydrothermal vents etc.
As they need extreme temperature, its very hard to study
them under laboratory conditions.
Also that some members can produce heat by
themselves (compost and garbage landfills).
Eg : Cyanidium caldarium,
Chaetomium thermophile
11. Deinococcus-thermus is a small group of eubacteria
which can thrive environmental hazards.
Stains Gram positive (thick cell wall) but possesses an
outer membrane, similar to the Gram negative cell wall.
Several thermophilic bacteria comes under this group.
It is the source of heat resistant enzyme- taq
polymerase, which is well used in PCR.
The enzyme is isolated from Thermus aquaticus.
12. Grand Prismatic Spring and Midway Geyser Basin-
Yellowstone National Park, USA
Source: Internet
13. CLASSIFICATION OF THERMOPHILES
1. Obligate thermophiles
Also known as extreme thermophiles.
Temperature range is 80-1220
C.
Membranes and proteins are unusually stable at
these extreme temperatures.
For this reason, most biological processes utilize
thermophilic enzymes because of their ability to
withstand intense heat.
Many of this group can resist radiation too.
Eg: Methanopyrus kandleri, can survive and
reproduce at 1220
C, Sulfolobus spp , Pyrococcus
spp, Pyrodictium spp (optimum of 1130
C)
14. Most of the members require elemental sulfur for
growth.
Anaerobic members use sulfur as electron acceptor
instead of oxygen in cellular respiration.
Some are lithotrophs that oxidizes sulfur to sulfururic
acid as an energy source.
Such organisms require a very low pH and hence
known as thermoacidophiles.
Inhabits regions associated with volcanic eruption viz;
hot, sulfur rich, acidic regions such as hot springs,
natural geysers, fumaroles etc .
15. HABITATS OF EXTREMOPHILES
Hot spring situated in Atlanta, USA
Courtsey:
http://www.idahohotsprings.com/destinations/atlanta/atlanta_hot_
springs_01.jpg
16. Castle Geyser, Yellowstone National Park, USA
Courtesy:
http://upload.wikimedia.org/wikipedia/commons/4/49/Steam_Phase_eru
ption_of_Castle_geyser_with_double_rainbow.jpg
18. Thermoacidophiles
Requires both high temperature and highly acidic environment
for optimum growth.
Preferred temperature range is 70-800
C and have an optimum
pH range of 2-3.
All the organisms discovered belongs to the Domain Archae,
so far.
They can thrive in acidous and sulfur rich environments.
Instead of cell wall, possesses a unique membrane composed
of tetraether lipoglycan, which gives the unusual stability for
the bacteria.
Eg: Thermoplasma acidophilum and T.volcanium
19. Facultative Thermophiles
Rare group of organisms that can live both in higher
temperature and normal temperature are referred to
as facultative thermophiles.
These organisms can live at 200
C, and have an
optimum of 500
C. Maximum temperature that they
can survive is 600
C.
Eg: Bacillus flavothermus
20. ACIDOPHILES
Microorganisms that lives in highly acidic
environments are called as acidophiles.
The pH range is 1-5.
Some members that mainly found in the drainage of
coal mines are able to oxidize sulfur into sulfuric
acid.
Mechanism of action is that they have a proton
pump machinery to eliminate protons from the
cytoplasm of the cell to maintain low pH.
Eg: Pyrodictium, Picrophilus, Ferroplasma,
Sulfolobus
21. ALKALIPHILES
These are extremophilic microorganisms which thrives
in roughly alkaline environments (8-11), and have an
optimum of pH around 10.
Organisms which needs high pH to survive are called
as obligate alkaliphiles.
There are facultative alkaliphiles and haloalkaliphiles
(needs salty environment as well).
Most of the alkaliphiles possess a bacillus morphology.
Eg: Bacillus halodurans C125,
Bacillus firmus OF4
22. Two methods for surviving
1. The cell will be having a unique cellular
machinery that works best in alkaline range of
pH.
2. The cell will have to acidify the cytosol to nullify
the effect of the high pH outside the cell.
23. Experimental studies revealed that the cytosolic
enzymes of alkaliphiles functions best in a neutral
pH range (7.5-8.5).
This shows that for surviving in highly alkaline pH,
the cell must have some pH regulatory mechanism
to protect the plasma membrane.
The mechanism is that the cell wall contains acidic
polymers composed of residues such as
galacturonic acid, gluconic acid, glutamic acid,
aspartic acid, and phosphoric acid.
This protects the PM by preventing the entry of
hydroxide ions and allowing the entry of sodium
(Na+
) and hydronium ions(H+)
24. XEROPHILES
A xerophile (from Greek xēros , meaning "dry",
and philos, meaning "loving"), is
an extremophilic organism that can grow and reproduce
in conditions with a low availability of water.
Water activity (aw) is a measure of the amount of water
within a substrate an organism can use to support
sexual growth.
Xerophiles are often said to be "xerotolerant", meaning
tolerant of dry conditions. They can survive in
environments with water activity below 0.8.
Endoliths and halophiles are often xerotolerant.
Eg: many molds and yeast,
Trichosporonoides nigrescens
25. HALOPHILES
This group comprises microorganisms that can thrive in
high salty environments such as The Great Salt Lake
and Dead Sea.
Most of the halophiles belong to the Domain Archae.
Eg: Salinibacter ruber
There are eukaryotic halophiles such as Dunaliella
salina (algae) and Wallemia icthyophaga (fungus).
Extreme halophiles/obligate halophiles-adapted to
survive high salt concentrations
Organisms from Dead Sea often requires nearly 33%
salt (sea water has only 3%), and the inoculating loop
must be dipped in a saturated salt solution to isolate
them.
Microorganisms live in such high salinity are termed as
extreme halophiles
26. Mechanism
Mainly employ two mechanism to prevent desiccation
through osmosis.
Both strategies work by increasing the osmotic
concentration of the cell.
1.In first method (followed my most halophiles including
bacteria, archae etc) organic compounds are accumulated
in the cytoplasm.
They are known as osmoprotectants or compatible
solutes.
It include sugars, aminoacids, polyols, betaines etc.
These compounds can be synthesised or accumulated
from the environment.
Eg: Ectothiorhodospira halochloris
27. 2. The second is the selective influx of potassium
ions (K+
) into the cytoplasm.
This adaptation is restricted to moderately
halophilic organisms.
The entire intracellular machinery (enzymes,
structural proteins etc) is highly adapted to
withstand the high saline environment.
Eg: Bacteria comes under the Family
Halobacteriaceae
The 16S rRNA studies opens a broad range of
information on the field of evolution.
28. ENDOLITHS
Endolith is an organism (archae, bacterium, fungus,
lichen or algae) that lives in nutritionally poor
environments such as inside a rock or something.
Particularly interesting in the area of astrobiology
(exobiology).
These organisms opens a clue for life beyond
earth. There are chances of having life on endolithic
environments such as mars and other planets.
29. Characteristics
Endoliths have been found in rocks down to the depth of
3 km.
It is not known that whether this is the limit since digging
to the deep is highly expensive.
The major threats to live in such depth is the high
temperature.
Recently discovered strains can reproduce at 1210
C.
All the discovered organisms are autotrophs.
Some utilize gas or dissolved nutrients from water
moving through fractured rocks
Others may incorporate inorganic compounds found in
their rock substrate (possibly by excreting acids to
dissolve the rock).
30. Endoliths can be classified into
Chasmoendoliths
Colonizes fissures and cracks in the rock (chasmo-
cleft)
Cryptoendolith
Colonizes structural cavities within porous rocks,
including spaces produced and vacated by
euendoliths (crypto = hidden)
Euendolith
Penetrates actively into the interior of rocks forming
tunnels that conform with the shape of its body(eu =
good, true).
31. Endolithic life form found inside an Antarctic rock
http://en.wikipedia.org/wiki/File:Cryptoendolith.jpghttp://
en.wikipedia.org/wiki/File:Cryptoendolith.jpg
32. Obligate Anaerobes
Microorganisms which grow strictly in the absence of molecular
oxygen are called as obligate anaerobes.
For these, oxygen is a toxin
For energy generation, they must employ fermentation or anaerobic
respiration pathways.
The toxic forms of oxygen are Singlet Oxygen(O2
), Superoxide
radicals (O2
-
), peroxide anion (O2
2-), and hydroxyl radical (OH).
Some obligate anaerobes are Clostridium spp, Methanococcus and
Methanopyrus
Microorganisms which can live both in the presence and absence of
oxygen are known as Facultative Anaerobes.
They can utilize oxygen if available or, continue their growth by
fermentation and anaerobic respiration.
Eg: Bacillus anthracis, Escherichia coli
33. An anaerobic work chamber and incubator
Fig: 6.15 page no:129, Prescott, Harley and Klein’s
microbiology
34. To routinely grow and maintain in pure cultures,
reducing media which stored in ordinary, tightly packed
tubes is been used.( media containing thioglycollate
or cystein)
For culturing in petriplates, sealed boxes and jars in
which oxygen removed completely is been used.
Sometimes, certain chemicals which can produce
hydrogen and carbon di oxide will be added and the so
formed hydrogen will be incorporated with the oxygen
present in the container to yield water
This water can be utilized by the microorganisms.
The most advanced system is that the media used for
culture will be containing an enzyme- oxyrase which will
bind with oxygen and eliminate as water. No addition of
extra chemicals or hydrogen is needed.
35. Radiation
Although most living things are sensitive to radiation,
there are some microorganisms which can resist high
levels of radiation.
Deinococcus radiodurans is the radioresistant
organism discovered so far which is a eubacteria.
Their ability to withstand radiation is more than that of
endospores.
They can survive exposure to radiation doses as high as
15,000 Grays. This much radiation is 1500 times the
dosage that would kill a human.
The mechanism for this extraordinary resistance lies in a
unique arrangement of its DNA that facilitates a rapid
repair of radiation damage.
It is similarly resistant to many mutagenic chemicals.
36. Barophiles
Microorganisms that can survive under immense hydrostatic
pressure.
Generally found in ocean floors where pressure exceeds
300 atm (38 MPa).
Some have been found at the bottom of the Pacific Ocean
(Mariana Trench-10500 m) where pressure often exceeds
117 MPa.
These organisms cannot grow in pressure below 400-500
atm
True obligate barophiles also comprises bacteria which
present in the gut of holothurians and amphipods
(crustaceans).
Eg: Photobacterium, Shewanella, Colwellia
Some thermophilc archae such as Pyrococcus spp.,
Methanococcus jannaschii are barophiles too.
37. SOME INTERESTING FACTS
Halomonas titanicae- the bacterium which is
responsible for rusting of RMS Titanic.
Pseudomonas putida (super bug) is a genetically
engineered bacteria which literally “eats” petroleum
products. These are very much useful in oil spills.
GFAJ-1 is a strain of rod shaped bacteria in the
family Halomonadaceae which is an extremophile,
highly resistant to the dangerous poison-Arsenic.
There are chances of life forms beyond earth and the
field of study is known as astrobiology.
39. The study of origin, evolution, distribution, and
future of life in the universe and life forms that are
extraterrestrial.
Astrobiology arises a question whether life exists
beyond Earth and if so, how it can be detected by
humans.
Nucleic acids might not be the only biomolecules
which codes for life.
Astrobiology makes use
of physics, chemistry, astronomy, biology, molecula
r biology, ecology, planetary science, geography,
and geology to investigate the possibility of life on
other worlds and help recognize biosphere that
might be different from the biosphere on Earth.
40. Recent advances in planetary science have
changed fundamental assumptions about the
possibility of life in the universe, raising the
estimates of habitable zones around other stars
and the search for extraterrestrial microbial life.
The possibility that viruses might also exist
extraterrestrially has been proposed. Efforts to
discover life on Mars, either currently or in the past,
is an active area of research.
Europa has emerged as one of the top locations in
the Solar System in terms of potential
habitability and the possibility of
hosting extraterrestrial life due to the presence of
liquid water (somewhat an ocean).
41. REFERENCES
Precott, Haarley and Kleins Microbiology by Willey,
Sherwood and Woolverton. (5th and 8th editions)
Microbiology - An Introduction (11th Ed)(gnv64)
Tortora
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC98
975/
http://library.thinkquest.org/CR0212089/therm.ht
m
http://www.mhhe.com/biosci/genbio/raven6b/gra
phics/raven06b/enhancementchapters/raven30_
enhancement.html
http://www.mapoflife.org/topics/topic_354_Extre
mophiles-Archaea-and-Bacteria/