Researchers Find 5 Strains of the Bacterium Enterobacter from Areas On Board the ISS
Researchers have discovered five strains of the bacterium Enterobacter from areas aboard the International Space Station (ISS). They are now calling for further careful research to figure out whether continuous exposure to microgravity could cause potentially dangerous mutations.
Nitin Singh and Daniela Bezdan from the Biotechnology and Planetary Protection Group at the Jet Propulsion Laboratory of the California Institute of Technology, US-led, a team who published a paper in the journal BMC Microbiology. In their work, they outline a genomic analysis of Enterobacter collected from the toilet and gym areas of the space station.
This form of bacteria is widespread on Earth and is linked to a range of sometimes serious human conditions, such as septic arthritis, osteomyelitis, skin and soft tissue damage and lower respiratory tract infections. Some strains even exhibit resistance to multiple antibiotics.
In sequencing the samples taken from the ISS, the team found that all five strains belonged to one species, E. bugandensis.
The members of the Enterobacter genus have been widely studied and sequenced, leading to a library of 1291 full genomes.
But, when Bezdan and her team ran the numbers on the space station microbes, they discovered that they were similar to only three, which are rare ones, at that. They report similarities with strains identified to date only once – one recovered from neonatal blood in a Tanzanian patient, another from a neonatal urine sample in the US, and the third from a 72-year-old woman with multiple health problems.
Overall, the researchers report, the eight strains made up a unique ecotype.
The ISS strains all had genes linked to drug-resistance. But, they did not contain combinations linked with high infection rates. Regardless, the results are enough for the researchers to call for a warning.
Singh explained that due to the multi-drug resistance results for these ISS E. bugandensis genomes and the heightened possibility of the pathogenicity they have identified, these species could pose important health considerations for future missions.
Singh added that it is important to note that the strains discovered on the ISS were not virulent, which means they are not an active threat to human health, but something to be watched. The authors also used computer analyses to predict that there was a 79% probability that the bacteria may potentially result in disease, given the right conditions.
Moreover, the authors note a degree of uncertainty concerning the development of the strains due to the highly unusual conditions where they live.
Co-author Kasthuri Venkateswaran explained that whether or not an opportunistic pathogen such as E. bugandensis causes disease and how much of a threat it is, is based on numerous factors, such as environmental ones. Thus, further in vivo studies are required to ascertain the impact that conditions on the ISS, including microgravity, other space, and spacecraft-related factors, could have on pathogenicity and virulence.Imprint
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