Although tardigrade are tiny creatures of comic appearance, they are one of the most optorous living species. Scientists have managed to discover that some individuals can boast another superpowerful property, an unexpected protective fluorescent shield that repels deadly ultraviolet radiation.
Tardigrade, also known as water bears or long-lived beetles, are microscopic creatures that live on land, in freshwater and a small number in the seas. Their body size ranges from a few microns to one millimeter. Their body is worm-shaped and stocky, divided into four segments and there are a couple of limbs on each segment.
However, their ability to survive inspires awe. These creatures can survive in the vacuum of space, at extreme temperatures and under extreme pressure, and they can withstand intense ionizing and ultraviolet radiation.
One of their survival tactics is to have the ability to shrink into a state of hibernation in which they can survive for decades, while at the same time producing proteins that protect their cells.
Another protective mechanism has now been discovered that seems to help tardigrades cope with potentially deadly ultraviolet light, and that is a kind of fluorescent substance that absorbs such radiation and then releases energy like blue light.
"Our study suggests that these creatures can survive in the driest and sunniest places on Earth," said Dr. Sandep Esvarapa, co-author of the study. In an article published in the magazine Bayoloji Letters, Esvarapa and his colleagues state that they found a new type of tardigrad in a sample of moss that was caught on the wall of their institute.
When both found species, called Paramacrobiotus BLR strain, and the other, H exemplaris, were exposed to ultraviolet light for 15 minutes, only the first survived. To their surprise, the surviving species emitted blue light during the exposure. To investigate this phenomenon in more detail, he covered UV-sensitive tardigrade with this fluorescent substance. The results showed that the extract of this substance provided at least partial protection, because half of the X exemplaris managed to survive for a few days. "There are other species that show tolerance to UV radiation, but Paramacrobiotus BLR is the only one that has fluorescence as a mechanism to resist this deadly radiation," emphasizes Esvarapa.
Professor Lukasz Kaczmarek, an expert on tardigrade from the Polish University "Adam Mickiewicz", who did not participate in this research, believes that this study supports previous works that show the possibilities of using substances that produce tardigrade to protect other organisms from harmful environmental conditions.
However, Kachmarek adds that the team failed to identify a substance that provides protection from ultraviolet radiation, noting that that protection may not come from fluorescence, but perhaps from some proteins.
I honestly didn’t know anything about the water bear but I read the article carefully!