44 / 49
Page 118
conferenceseries
.com
Volume 7, Issue 2 (Suppl)
J Ecosyst Ecography, an open access journal
ISSN:2157-7625
September 18-20, 2017
September 18-20, 2017 Toronto, Canada
Joint Conference
International Conference on
International Conference on
Environmental Microbiology and Microbial Ecology
&
Ecology and Ecosystems
J Ecosyst Ecography 2017, 7:2 (Suppl)
DOI: 10.4172/2157-7625-C1-030
Microbial life on Mars: The effect of the Martian environment on
Halobacterium salinarum
NRC-1
Sebastian Sjoestroem
1, 2
, Stefan Leuko
1
, Per-Åke Nygren
2
and
Petra Rettberg
1
1
German Aerospace Center, Germany
2
Royal Institute of Technology, Sweden
A
strobiology is the study of life, its origin, evolution and distribution in the universe. Some of the best models for extraterrestrial
life studies are found in extreme environments on Earth that are similar, in certain aspects to the terrains on Mars. Climate
models show compatibility with transient, night-time liquid brines, shifting the focus to halophilic extremophiles. This project was
designed to simulate the harsh climate of Mars and study how the archaeon
Halobacterium salinarum
sp. NRC-1 copes with radiation,
temperature changes, desiccation and different brines compositions adapted from. Solar UV: 200-400 nmwas emulated at the German
Aerospace Center DLR, in Cologne, Germany and
Hbt. salinarum
was exposed in liquid Martian brine analogues (MBAs) as well
as desiccated, and survival was determined. The effects of diurnal-nocturnal cycling were investigated for temperature alternations;
4, -20ºC and -80°C. In the MBAs that supported survival of
Hbt. salinarum
, desiccation was the most harmful of the tested Martian
conditions. However the desiccated samples had an increase in relative survival of diurnal-nocturnal cycling compared to liquid
MBAs. The survival following irradiance was dependent on the brines with F10, (200-400 nm)-values ranging from 14-360 kJ∙m-
2 and some of the MBAs displayed protective qualities. Adding yeast extract, as organic nutrient to the brines also proved to be
harmful to the organism.
Hbt. salinarum
is unlikely to thrive on Mars, as simulated in this project, but their long-term survival is not
unimaginable. Halophiles are robust and should be considered both in questions of colonization- and unwanted contamination of
Mars.
Ssjostro@kth.se