Response of Antibiotics and Bacteria in a Microgravity Environment
SSEP Mission 4 to the International Space Station
Response of Antibiotics
and Bacteria in a
Microgravity Environment
Co-Principal investigators: Paxton Ellul, Ashley Miller, and Haley Dole
12 grade
Teacher Facilitator: Patrick Gillespie
Traverse City West Senior High School
Flight Experiment, Mission 3 to ISS
Response of Antibiotics and Bacteria in
Microgravity
Essential Question: How does bacteria growth and antibiotics respond together in a
microgravity environment?
Hypothesis: We believe that the bacteria may grow to a higher concentration in microgravity
but the antibiotic dosage will still manage to fully treat the bacteria grown.
Experiment Design
Section C- This section contained our
antibiotic, Cephalexin, that when mixed
in with our staphylococcus epidermidis
should kill the bacteria cultures.
Section AInside this chamber we inclosed
Staphylococcus Epidermidis in a
powdered form that would be
ready to react with the growth
serum.
Section B- Within the middle section of the FME tube we placed the
bacteria growth serum that will be mixed with the bacteria during the
experimental process.
Experiment Design
● Five days prior to coming back from the ISS a clamp was removed from
our test tube that allowed the bacteria and the growth serum to mix. The
bacteria then grew for three days aboard the ISS.
● Two Days prior to returning to earth the last clap was removed exposing
the antibiotic to the the growing bacteria.
While the astronauts performed these
tasks we did the same for control experiment.
Spectrophotometry Test Results
Wavelengths in Nanometers
Control Experiment
Transmittance
Microgravity Experiment
Transmittance
590 nm
0.1
0.4
600 nm
0.2
0.6
610 nm
0.2
0.6
620 nm
0.2
0.6
630 nm
0.2
0.6
640 nm
0.2
0.6
650 nm
0.2
0.6
660 nm
0.2
0.4
Control Experiment
Microgravity Test
Experiment
Conclusion
After being sent to Munson’s Laboratory, it was concluded that there was no viable Staphylococcus
Epidermidis in either the microgravity or control experiment sample. The antibiotic, Cephalexin, with
a heavy dosage worked just as effectively in microgravity. Unfortunately the laboratory lacked the tools to
do a quantitative measurement on the dead bacteria and they also reported some contamination in our
samples.
Why was the control experiment able to absorb more light than the other in our Spectrometer test?
We theorize that because there was the same amount of Cephalexin in each of the tests and they were
mixed to the same degree, the difference may have come from a variation in the amount of dead bacteria
in the solutions. The control experiment absorbed more light in the spectrometer than the microgravity
experiment which may mean that it had a greater amount of dead bacteria in its solution. In the
microgravity experiment the bacteria had more spatial room meaning that immediately more surface area
would have been exposed to the antibiotic; allowing it to kill the bacteria faster than the control experiment
which had less bacteria exposed. The control experiment therefore could have kept growing bacteria as
the antibiotic was fighting it for a longer period of time than the microgravity experiment therefore
producing more dead cultures and transmitting less light in the spectrometer.
Collaborators and Community
Partners
Collaborators
Community Partners
Traverse City Area Public Schools
Traverse City West Senior High School
Munson Healthcare
Center for the Advancement of
Science in Space
Special thanks to SSEP for giving us
this experience!
National Center for Earth and
Space Science Education
Dow Chemical Company
DTE Energy Foundation
Salamander Technologies
B and E Enterprize