Cyanobacteria found living 600 meters underground without sunlight

October 2, 2018 by Bob Yirka, Phys.org report
Cyanobacterial markers in deep core samples revealed by a Life Detector Chip immunoassay. Credit: PNAS

A team of researchers from Spain, Germany and the U.S. has found a type of cyanobacteria that is capable of living more than 600 meters underground—in the absence of sunlight. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of the cyanobacteria and what they found.

The Rio Tinto region in Spain has long been a stand-in for Mars—the landscape there is red due to an abundance of iron and sulphur minerals. Because of its similarities to Mars, researchers have studied taken from above and underground, looking to better understand what sorts of life can exist in such a barren place. In this new effort, the researchers drilled a 613-meter borehole to study rock samples far below the surface. The team found living in cracks and crevices within samples. Other bacteria have been found living far below the surface in the area, but cyanobacteria are different. Up until now, scientists believed they needed to survive.

Cyanobacteria derive energy through photosynthesis—hence the need for sunlight. They are also some of the oldest forms of life on the planet. Prior research has suggested that they were responsible for adding oxygen to the atmosphere, making it possible for other forms of life to evolve.

Viable cyanobacterial cells (red fluorescent signals) attached to rock fragments. Credit: PNAS

Surprised by their find, the researchers went back for more samples using more stringent protocols to ensure that they were not contaminated. They found groups of cyanobacteria living in air pockets in rocks.

To learn how the cyanobacteria are able to survive without sunlight, the team examined them under a microscope. They found that in most respects, the cyanobacteria were the same as their cousins living on the surface in the surrounding area. When testing the air in the pockets, they discovered that the tiny creatures were consuming hydrogen gas as evidenced by lower hydrogen levels where the cyanobacteria were found. They also found evidence that the subsurface cyanobacteria had one small adaptation to their photosynthetic system that allowed them to use a "safety valve" to produce energy. In other cyanobacteria, the valve is used to release excess energy to prevent overheating when sunlight is abundant.

Explore further: Rainfall after drought caused explosion of cyanobacteria populations

More information: Fernando Puente-Sánchez et al. Viable cyanobacteria in the deep continental subsurface, Proceedings of the National Academy of Sciences (2018). DOI: 10.1073/pnas.1808176115

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KBK
5 / 5 (2) Oct 02, 2018
Is there life on mars?

Probability is creeping up toward the 100% mark.

When found not if, the operative method of function of such life should prove interesting.

If it turns out to be 'DNA', with large similarity or a perfect enough match, that should mess with a lot of minds.

As...... a completely different form of life would not cause as many problems with the 'considered' record of life on earth and galactic proposals and projections for life in the universe.

A match would create a shitstorm. Not enough words to describe it.
torbjorn_b_g_larsson
not rated yet Oct 02, 2018
As...... a completely different form of life would not cause as many problems with the 'considered' record of life on earth


I don't see how. We expect there is a fair chance that local transpermia happens between habitable planets due to crust ejecting large impactors. Say in our system Earth may have seed Mars and ice moons out to Saturn during the first 4.5 billion years. So we may see life forms with DNA in Mars crust.

That goes both ways of course, but we certainly have seen no sign of genes that, say, originated on Earth, evolved later on Mars, and then returned to cause some type of problem with the known record - it nicely trees all populations known to date (as does fossils and both's biogeographical spread).
Thorium Boy
1 / 5 (2) Oct 03, 2018
Is there life on mars?

Probability is creeping up toward the 100% mark.

When found not if, the operative method of function of such life should prove interesting.

If it turns out to be 'DNA', with large similarity or a perfect enough match, that should mess with a lot of minds.

As...... a completely different form of life would not cause as many problems with the 'considered' record of life on earth and galactic proposals and projections for life in the universe.

A match would create a shitstorm. Not enough words to describe it.


You won't find it with probes with 486 Intel processors for brains.

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