The strains found in space were not pathogenic to humans.
Strains of the bacterium Enterobacter, similar to newly found opportunistic infectious organisms seen in a few hospital settings, have been identified on the International Space Station (ISS). The strains found in space were not pathogenic to humans, but researchers believe they should be studied for potential health implications for future missions, according to a study published in the open access journal BMC Microbiology.
Researchers at the Jet Propulsion Laboratory, California Institute of Technology, USA investigated five strains of Enterobacter that were isolated from the space toilet and the exercise platform on the ISS in March 2015 as part of a wider effort to characterize the bacterial communities that live on surfaces inside the space station. To identify the species of Enterobacter collected on the ISS and to show in detail the genetic make-up of the individual strains, the researchers compared the ISS strains to all publicly available genomes of 1,291 Enterobacter strains collected on Earth.
Comparing the genomes of the five ISS strains to the three clinical Earth strains allowed the authors to get a better understanding of whether the ISS strains showed characteristics of antimicrobial resistance, if they had gene profiles similar to those found in known multi-drug resistant bacteria, and to identify genes related to their ability to cause disease.
The authors found that the ISS isolates had similar antimicrobial resistance patterns to the three clinical strains found on Earth and that they included 112 genes involved in virulence, disease and defense. While the ISS E. bugandensis strains were not pathogenic to humans, the authors predicted via computer analyses, a 79% probability that they may potentially cause disease. However, analyses in living organisms should be carried out to confirm this.