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Experiment/Payload OverviewStreptococcus pneumoniae Expression of Gene in Space (SPEGIS) will examine the behavior and growth of bacteria in microgravity and investigate the effects of the space environment on the gene expression, protein production, and virulence of the bacteria Streptococcus pneumoniae. The data collected will also provide insight on what types of bacterial infections may occur during long-duration space missions and the risks to crew members.
Principal Investigator
Information Pending
Payload Developer
Ames Research Center, Moffett Field, CA, United States
National Aeronautics and Space Administration (NASA)
Sponsoring Organization:Exploration Systems Mission Directorate (ESMD)
ISS Expedition Duration:April 2007 - October 2007
15
Previous ISS MissionsWhile SPEGIS is a new experiment, other studies of microbial virulence have been conducted aboard ISS.
The Streptococcus pneumoniae Expression of Genes in Space (SPEGIS) experiment investigated S. pneumoniae gene expression and protein production in the space environment. S. pneumoniae is an important human pathogen (disease causing) and the leading cause of bacterial pneumonia (inflammation of the lungs with congestion), meningitis (inflammation of the membrane covering the brain and spinal cord), and otitis media (ear infection). Importantly, this pathogen has been isolated previously from the crew preflight and related bacteria are found in the spacecraft environment. Experiments were performed to identify and characterize S. pneumoniae genes and proteins, which are differentially expressed in response to the space environment and compare microgravity-induced genes and proteins to those expressed during postflight rodent infection.
S. pneumoniae is a respiratory microbe normally found in the upper respiratory tract of approximately 40 percent of the healthy human population. The identification of specific S. pneumoniae virulence factors and cellular and molecular processes may aid scientists in furthering the understanding of how this bacteria causes infection. This data may aid in the design and development of new antimicrobial drugs. This experimental approach will result in new information about a significant human pathogen, add to our knowledge about the S. pneumoniae pathogenic mechanism, and also provide basic information on the bacterial model system of gene and protein expression in the space environment.
Identification of the global genetic responses undergone by S. pneumoniae in reaction to space will enable this single-flight experiment to determine if the spacecraft environment exerts a selective pressure on microbial contaminants, leading to increased virulence and contributing to increased health risks to the crew. Results from SPEGIS will also provide information on the threat of opportunistic pathogens in the space environment, which will assist in the development of diagnostic tools to monitor the atmosphere and surfaces (air, soil, and food) for the presence of these microbes. Further, identification of spaceflight alterations to genes and proteins involved in bacterial proliferation and mutation will provide targets for pharmacological intervention, which will ultimately facilitate long-term exploration of the Moon and Mars.
Earth ApplicationsAnalyzing and understanding the mechanisms utilized by S. pneumoniae to adapt to microgravity will likely lead to the development of novel methods to combat newly emerging drug-resistant strains, which could greatly assist in disease prevention and management on Earth.
Vials containing bacterial cultures will be loaded into the SPEGIS Canister Assembly. A total of three canisters will be flown on the space shuttle. Each Canister contains three 8 ml polypropylene vials. The vials are inserted into vial jackets to improve contact and enhance thermal transfer. The compression pad eliminates space between the vials and canister lid.
Operational ProtocolsThe SPEGIS payload will be launched while stored at +4 degrees C in the Microgravity Environment Research Locker/INcubator (MERLIN). After the orbiter docks with the ISS, the canisters will be transferred to the Minus Eighty Laboratory Freezer for ISS (MELFI) for +2 degrees C cold stowage. For the on-orbit incubation phase, the canisters will be transferred back to MERLIN and then incubated at +37.5 degrees C. After incubation, the canisters will be transferred back to MELFI for -95 degrees C cryopreservation. The samples will be returned to Earth while stored in the Double Coldbag with ICEPACs at -32 degrees C, which will maintain the integrity of the frozen samples for post-flight analysis by the investigator.
SPEGIS is a recently completed investigation which is undergoing data analysis, final results are pending. (Evans et al. 2009)