Surprising discovery: marine microorganisms can produce oxygen without sunlight

It is known that there would be no oxygen on Earth without sunlight, the main component of photosynthesis. But a team of researchers from the University of Southern Denmark, in their study recently published in the journal Science, made the surprising discovery of a strange marine microbe that does not perform photosynthesis, but still generates oxygen without sunlight.

There seems to be a lot more going on in the deep, dark ocean waters than you might think. Countless unseen microorganisms go about their daily lives in the water columns, and now researchers have discovered that some of them produce oxygen in an unexpected way.

Ocean microbes

Marine microbes are single-celled ocean microorganisms that make up more than 98% of ocean biomass, and include bacteria, archaea, eukaryotes, and viruses. They are microorganisms that cannot be seen by the human eye.

A press release from this university says that few microbes are known to produce oxygen without sunlight, but so far it has only been discovered in very limited quantities and in very specific habitats.

According to the statement, the researchers, after their laboratory study of various microbes in the depths of the ocean, discovered a type of microbes that can live in dark, low-oxygen places in the depths of the ocean.

The researchers emphasized that the interesting thing about these microorganisms is that they are able to produce oxygen, without the need for sunlight, as most of the organisms that generate oxygen are plants, algae and cyanobacteria, and they do so through the process of photosynthesis.

Microbes that make oxygen

Researchers say that those microbes that are able to produce oxygen in the dark, which were discovered in this exciting study, are a type of microbe called Nitosopumilus maritimus, one of the smallest creatures on Earth, and one of the single-celled microorganisms that do not have a nucleus.

According to the study, researchers say that these microbes are abundant in the oceans and play an important role in the nitrogen cycle, as they oxidize ammonia to produce nitrogen that requires oxygen, so these organisms often live in oxygen-rich areas in the ocean.

However, the interesting discovery that the researchers made is that this type of microbes can also survive in the dark regions of the ocean, where there is little oxygen, something that has puzzled scientists for a long time.

How do microbes produce oxygen?

To examine and study these microbes, the researchers produced cultures of archaea in airtight containers kept in the dark, then artificially reduced oxygen levels in the containers to mimic the deepest regions of the ocean. On the rise again.

Although the researchers say they aren't entirely sure how the microbes generate the supplemental oxygen, they believe that the microbes Nitosopamylas maritimus produced the oxygen by using the microbes to use a different biological method than they knew - a mechanism they had not seen before.

On the other hand, the researchers were able to demonstrate that this biological mechanism used by the microbes led to the production of both oxygen and nitrogen oxide, a mixture of products not seen in known pathways for oxygen generation.

Researchers believe that these ammonia-oxidizing archaea are among the most numerous living organisms on Earth, and scientists have known for more than a decade that they play a major role in the oxidation of ammonia, but their ability to produce oxygen is surprising.

It is expected that if these archaea are so widespread in the oceans, this could indicate that this mechanism may be present in many other organisms as well. And if this way of life is widespread in the oceans, it certainly prompts us to rethink our current understanding of the marine nitrogen cycle.

This is what prompts researchers to be their next steps to verify this phenomenon, which they discovered in their laboratory in water depleted of oxygen in different regions of the oceans around the world.