Scientists are studying microorganisms under extra-terrestrial conditions to better understand how they grow on Earth – and let them produce more drugs
When exploiting or studying microorganisms, microbiologists in research and industrial laboratories provide them with a cozy ambient, so that the microbes can optimally grow to yield high amounts of biomass or biotechnologically-relevant products for further analyses. Under natural conditions though, microbes are often stressed by changing environmental parameters, lack of nutrients or presence of competing species.
Microorganisms can cope with these stresses by cellular adaptations, e.g. by modifying the expression of their genes and producing specific substances like antibiotics to fight competitors. This metabolism, which is not required for growth and reproduction under “normal” conditions, is referred as the “secondary metabolism,” and is crucial for survival of microorganisms growing in nature. The products (secondary metabolites) are often highly bioactive drugs interesting for medicine and biotechnology.
Analysis of the genome sequences of microorganisms, and in particular of soil-inhabiting species from the genus Aspergillus (filamentous fungi) and Streptomyces (actinobacteria), showed that many “secondary metabolism” genes are turned off – at least in the lab. In the quest for new drugs, scientists are trying to turn on these genes.
But how? By sending microbes to outer space, microbiologists collaborating with NASA are investigating if physical parameters like low gravity and high radiation are activating their secondary metabolism. The long-term vision is that, one day, space explorers might be able to grow their own medicine during their missions.
This is not a wild shot: It is already known since many decades that different physical laws are applied to microorganisms cultivated in the laboratory in comparison to those growing in nature. Thus, the often-heard science-fiction phrase “I will take you to a place you have never been before,” might well be used here. At least for microorganisms.
— by Corrado Nai