Long-term exposure of bacterial cells to simulated microgravity

摘要

Previous space flight experience has demonstrated that microorganisms are just as ubiquitous in space habitats as theyare on Earth. Numerous incidences of biofilm formation within space habitats have been reported; some of which wereidentified only after damage to spacecraft structures and irritation to astronaut’s skin occurred. As we increase theduration of spaceflight missions, it becomes legitimate to question the long-term effects of microgravity on bacteria. Tobegin this assessment, Escherichia coli K-12 strain MG1655 was grown for one thousand generations (1000G) underlow shear modeled microgravity. Subsequently, growth kinetics and the presence of biofilm were assessed in the 1000Gstrain as compared to a strain (1G) briefly exposed to LSMMG. Overall, the analysis revealed that (i) there was noobvious difference in growth kinetics between the 1G and 1000G strains, and (ii) although biofilm formation was notseen in the 1G strain it did in fact occur as exposure time increased. The results suggest that long-term exposure to thespace environment likely favors biofilm formation in many organisms.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.