Scientists have proposed a new way to detect alien microorganisms — an improved technique for forcing them to move using chemicals.
Alien microorganisms
Scientists have already studied quite a few rock samples from other planets and know that there are many structures that look very similar to living beings, or at least could be them. A recent study appeared in the journal Frontiers in Astronomy and Space Sciences that may help in the detection of alien life.
Its authors, scientists from Germany, pointed out that one of the characteristics of all living beings is the ability to move spontaneously toward or away from something. And biology knows at least one method to make single-celled organisms move. It is about the influence of the presence of chemicals, which is called “chemotaxis”.
Although this method has been known for a long time, nobody has ever thought about what substances should be used to make a single-celled creature, about which we know absolutely nothing, move. The researchers hypothesized that it could be the amino acid L-serine.
Tests on microorganisms
To prove that L-serine makes microscopic organisms move toward it, the scientists tested on two species of bacteria and one species of archaea. They are interesting because they are not related at all and live in dissimilar environments.
The very mobile bacterium Bacillus subtilis in the form of spores can withstand temperatures up to 100°C. In contrast, Pseudoalteromonas haloplanktis lives in Antarctic waters and tolerates a temperature range of -2.5°C to 29°C.
And the archaea Haloferax volcanii is quite unlike them. It’s a separate branch of life altogether. It inhabits the over-salted Dead Sea. There is little in common between all these microbes, but they live in extreme conditions.
Ice, thermal springs, over-salted bodies of water — all of these things can be found on Mars, or at least such conditions once existed there. With this sampling, scientists have covered a fairly wide range of possible life forms.
Research shows that L-serine makes them all move. Therefore, it can be expected to be the best option for robot-assisted detection of living organisms on other planets. However, the experimental setup will have to be reduced in size for this to happen.
According to phys.org
