Micro-6 (SpaceX-1)

Genotypic and Phenotypic Responses of Candida albicans to Spaceflight

Finding New Ways to Treat Infections in Space

Yeast. It’s a good thing. It makes bread rise, turns grape juice into wine, and is essential in the production of beer. And in our bodies, yeast–specifically the yeast Candida albicans–helps us maintain a healthy personal ecosystem. However, when our immune systems are stressed, Candida albicans can grow out of control. When that happens, yeast become so numerous that infections can result in the mouth, throat, intestines, and genitourinary tract.

Studying how Candida albicans responds to the microgravity of space flight aboard the International Space Station is the subject of a new experiment destined to launch on the SpaceX-1 flight, scheduled for liftoff from Cape Canaveral Air Force Station on October 7, 2012. The experiment is designed by Principal Investigator Sheila Nielsen, Ph.D., Associate Research Professor, Montana State University, Bozeman MT. Project Scientist Macarena Parra Ph.D.,  provides scientific guidance and direction specific to experiments on the space station.

Researchers chose the yeast Candida albicans because there¹s already a great deal of scientific understanding of the organism. Thanks to the extensive studies of Candida, the researchers will have a broad set of benchmarks, including the sequence of the entire genome, against which they can compare their results.

Designed to examine how spaceflight affects potentially infectious organisms, the experiment will provide new insights into better management and treatment of Candida infections if they occur. By comparing the cells grown in microgravity to cells grown in normal gravity, the research team will examine the susceptibility of the yeast to an antimicrobial agent. By developing stronger and better treatments for astronauts during long duration space flight, the experiment may yield results that help prevent and treat yeast infections among astronauts. Eventually this research may lead to an understanding of why yeast infections become more virulent when the immune system is stressed, and potentially deliver more powerful antibacterial treatments here on Earth.

Unique Environments Demand Specialized Equipment

Critical technology for the experiment is provided by BioServe Space Technologies at the University of Colorado, Boulder. The equipment consists of Group Activation Packs (GAP) stored in a flight-certified incubator at a temperature of 4 degrees centigrade. Each GAP contains eight Fluid Processing Apparatuses (FPA) shaped like test tubes but designed to meet the unique requirement of mixing fluids in microgravity. Each FPA contains an isolated amount of the microbial culture of Candida, plus a growth medium and a termination reagent or fixative. During the three-week flight aboard the space station, a crew member will begin the experiment by increasing the incubator temperature to 30 degrees centigrade, and then activate the FPAs by pushing the plunger to mix the Candida with a growth medium. After 24 or 50 hours depending on the sample, the experiment will be terminated by pushing the plunger deeper into the FPA which combines a fixative agent to effectively stop the growth of the yeast cultures.

Protecting the health of astronauts in space

After the yeast return to Earth from space, Principal Investigator Sheila Nielsen will examine changes to the genetics within the organism. The experiment will help researchers understand if the yeast is more virulent or infectious after exposure to a microgravity environment and, most importantly for future treatment, how they have changed to become more infectious. Identifying the change can potentially lead to development of more effective treatments.

According to Parra, the experiment could be of vital importance in protecting the health of astronauts in space. On Earth, life has evolved over millions of years in a 1 g environment. In space, living systems have to adjust to a different environment. Without gravity, microorganisms become more virulent, biofilms form more easily, and the immune system tends to get compromised. So, the more we know about the effects of living in microgravity, the better it is for humans in space.

Principal Investigator:  Sheila Nielsen, Ph.D., Montana State University

Project Scientist: Macarena Parra Ph.D., Ames Research Center

For more information, see the Space Station Research Explorer for the Micro-6 mission.