Introduction, The Quest for Exo Microbes, Extreme conditions in space, Effects of Space on microbes, Future Applications

2. Group Members:-
 Naveed ur Rehman
 Habib ur Rehman
 Nadeem Ullah
 Syed Ahson Naveed
 Nabeela Bakar
 Asma Sattar
 Saira Yousaf
 Ihtesham Serratia Bangesh

3. Outline
 Introduction
 The Quest for Exo Microbes
 Extreme conditions in space
 Effects of Space on microbes
 Future Applications

4. Exomicrobiology
Astro microbiology, or exo microbiology,
study of microorganisms in outer space.

5. Origin of Exomicrobiology
 Search for microbes in space has been linked to
Astrobiology.
 In fact Astro microbiology was created due to Cold War.
 First attempt NASA's Viking program in the 1975, in
which two Mars landers searched for biosignatures of
life on Mars.
 The results were largely inconclusive.

6.  For future space applications such as the quest of
microbial fuel cells. Eg, Methanogens
 To develop a life support system that enable humans to
live outside the earth’s environment. Eg, MELiSSA
 Biotechnological processes that are successfully used
on earth could be employed on space. Eg, Bio mining.

7. WHAT do we know ?
 No proof of any
extraterrestrial microbial life
has been found naturally.
 Check the mutation and
survival of microbes after
their deliberate exposure to
outer space.

8. How ?
Space can effect microbes in two
ways:
1: By Weakening the microbe
(leads to death)
2: By Strengthening the microbe
(leads to resistant form)

9. Planetary Exploration
 Most of the exploration attempts were on Mars due to its
promising environment and close proximity.
 Europa, Titan and Enceladus. All either had or have liquid
water.
 Titan has liquid hydrocarbons on its surface which may
support life based on these hydrocarbons.
 Mars has an atmosphere containing abundant amounts of
carbon and nitrogen, both essential elements needed for
life

10. Extreme conditions in Space
 Weightlessness/ Microgravity
 Increased radiation exposure
 Space Vacuum
 Thermal extremes
 High velocity micrometeoroids
Space studies on microbes
 Effect of basic parameters on microbes
 Applied aspects

11. Microbes in Microgravity
 Microgravity affect gene expression and growth
kinetics.
 Growth is affected by reduction Extracellular mass
transfer and motility.
 Microgravity also increase in virulence and Biofilm
production.
 Most of the studies related to microgravity are
simulated on earth in devices like clinostat.

12. Physical Effects of microgravity on
microbes
 EXTRACELLULAR MASS TRANSFER
 Transfer under gravity occurs through diffusion and
convection
 Convection is caused by relative densities of molecules
 In microgravity, convection is reduced and mass transfer
relies on diffusion only.
 This reduction of mass transfer is hypothesized to cause
a decrease in lag phase

13. Physical Effects of microgravity on
microbes
Cell Growth
 Cell concentration of E.coli was greater than 1 g.
 Presence of gravity leads to sedimentation and over
crowding and rapid nutrient depletion
 Within microgravity the microbes are better distributed
and leads to greater proliferation.

14. Physical Effects of microgravity on
microbes
Biofilm production
 Adherence is dependent on the forces acting on cell
 In microgravity, reduced fluid shear causes (S. aureus and P.
aeroginosa) causes decreased Hfq expression.
 Although virulence was decreased but cell adhesion was
enhanced.
 Hfq protein is a global post-transcriptional regulator that
plays a key role in gene expression. It results in decrease
secondary metabolite production.
 Deletion of the Hfq gene causes loss of secondary
metabolite production

15. Physical Effects of microgravity on
microbes
Cell size
 E.coli’s average volume of the spaceflight cells was 37%
of the earth controls.
 This reduced cell size was due to lower rate of diffusion
 The reduced cell size was also due to altered growth
rate.

16. Physical Effects of microgravity on
microbes
Virulence
 Flight-grown S. Typhimurium were more virulent in
mice
 The flight-grown S. Typhimurium had a lower lethal
dose (LD50) among the mice.
 They also died faster as compared ground mice.
 Hfq - a global translational regulator in Salmonella -
was found to be the key factor behind this increased
virulence

17. Exceptions to hyper-virulence and
T3SS
 Yersinia pestis and S. aureus have shown exception to
the the trend of microgravity induced hyper virulence.
 Yersinia pestis showed diminished proliferation and
virulence, and it had compromised T3SS function.
 T3SS( injectosome)
 Impairment of T3SS often renders the organism non-
pathogenic

18. List of Microorganisms tested in Outer Space
 The survival of some microorganisms exposed to outer space has
been studied using both simulated facilities and low Earth
orbit exposures.
 Examples are the following:
Bacteria and Bacterial Spores
Bacteria & bacterial spores Low Earth orbit Simulated conditions
Aeromonas proteolytica
Enterobacter aerogenes
Staphylococcus aureus
Escherichia coli
Bacillus subtilis

19. Archea
Organism Low Earth orbit Simulated
conditions
T7 phage
Canine hepatitis
Tobacco mosaic virus
Vaccinia virus
Organism Low Earth orbit Simulated conditions
Halorubrum chaoviatoris
Halobacterium salinarum
Methanosarcina sp. SA-21/16
Methanobacterium MC-20
 Bacteriophage/Virus

20. Organism Low Earth orbit Simulated conditions
Penicillium roqueforti
Mucor plumbeus
Aspergillus niger
Aspergillus oryzae
Euglena gracilis
Organism Low Earth orbit Simulated conditions
Zygosaccharomyces bailii
Saccharomyces ellipsoides
Rhodotorula rubra
 Fungi and Algae
 Yeast

21. Future applications
 Health assessment: diminish effectiveness of immune
system makes microbes potentially harmful and resistant
for onboard crew.
P. aeruginosa and S. aureus are opportunistic pathogens in
skin flora.
With the advent of antibiotic-resistant strains such as
MRSA, these species in particular can be life-threatening.
 Chemotherapeutic purpose: eight special fungi isolated
from the accidental site of nuclear power plant are sent to
space to see if they produce new compounds that could be
used as radiation therapy molecules.

22.  Vaccine development: virulance and growth factors can
contribute for the development of vaccines. Astrogenetix’s
space based Salmonella research have been successful in
formation of its vaccine.
 Secondary metabolite production: Monorden produce
by fungus humicola was increased. Actinomycin D by
Streptomyces plicatus also increased
 Creating habitable environment in outer space:
installing bioreactors on Mars which would run entirely on
cyanobacteria, providing biomaterial to initiate life.

23. References
 Artemieva, N. A., and B. A. Ivanov. 2004. Launch of Martian meteorites in oblique impacts. Icarus 171:183–196.
 Baker, P. W., M. L. Meyer, and L. G. Leff. 2004. Escherichia coli growth under modeled reduced gravity.
Microgravity Sci. Technol. 15:39–44.
 Mothersill, C., and C. B. Seymour. 2004. Radiation-induced bystander effects—implications for
cancer. Nat. Rev. Cancer 4:158–164.
 Zea L, Larsen M, Estante F, Qvortrup K, Moeller R, Dias de Oliveira S, Stodieck L and Klaus D (2017)
Phenotypic Changes Exhibited by E. coli Cultured in Space.Front. Microbiol. 8:1598.doi:
10.3389/fmicb.2017.01598