Thrust 2: Space Microbiology

Investigators: Jejelowo (Lead),Abdel-Rahman, Miranda, Saleh, Briggs, Pourmand, Rosenzweig

Microbial colonization of NASA equipment in space poses serious risks to both man and machine. Prior to its decommissioning in 2001, the Russian space station Mir was reported to have been eaten alive, with plastics, metal, and quartz glass windows showing signs of deterioration from fungi, bacteria and other microbes. Scientists are also concerned that microorganisms can cause infections or allergic diseases in astronauts because space travel compromises the immune systems.

With the development of the International Space Station and future missions to Mars, it is important to understand the origins, rates, and patterns of molecular mutations of (micro)organisms that co-habit with man in space explorations. Because of the potential health risks to astronauts and their contribution to the deterioration of space station materials, the understanding of molecular and genomic changes in an antigravity environment would be important in the long-term management of space stations and spacecrafts. In particular, microbial life forms are known to suffer from fast rates of mutation due to ionizing radiation. Microorganisms in space are hypothesized to be subjected to an increased rate of mutation because the level of radiation in space can be more than 500 times than that on Earth. We will use DNA sequencing as a tool to study fungal systematics and evolution. This work will involve large efforts in molecular and computational biology by researchers and students from TSU.

Objective 1. To understand the effect of space on microbial evolution using genomic techniques. Microbial life forms are hypothesized to undergo fast rates of mutation in space due to ionizing radiation. To understand how the high levels of radiation in space might alter terrestrial microbes, we intend to: 1) characterize the molecular sequences of select genes of all known fungal strains in manned space stations, 2) determine the evolutionary origin of these strains by comparison with Earth-based taxa, 3) investigate the pattern of synonymous and nonsynonymous differences between terrestrial and space fungal genome, and 4) identify genes that are subject to positive or neutral selection in space.

Objective 2. To understand the effects of space on microbial ecology, growth kinetic, morphology and virulence. Microorganisms exposed to space environment undergo changes in growth kinetics, morphology and virulence. To understand how radiation and microgravity affect growth kinetics and morphology, we will study growth parameters for fungal isolates obtained following exploration missions. The samples will be obtained from NASA JSC and used in comparative analysis with similar earth-based species.

Objective 3. To develop novel methods for controlling microorganisms in confined environments. Microbial colonization of surfaces in spacecraft is a major issue that impacts human health as well as the integrity of materials in the craft, as seen in Mir and the Space Station. Since it is often not possible or advantageous to apply antimicrobials or use mechanical methods to treat microbial colonization in a space travel setting, we will computationally design and model organic catalysts that can be attached to material surfaces that will degrade signals from bacteria thereby, preventing bacterial colonization, and synthesize and test these compounds for inhibition of bacterial colonization.