Strange creatures can survive without oxygen

What powers microscopic organisms instead of oxygen remains a mystery that scientists have yet to uncover. 

Henneguya salminicola - a parasite that lives inside salmon and "steals available nutrients instead of consuming oxygen directly", has a rather unique superpower that is able to survive without oxygen .

When examining Henneguya salminicola, the researchers noticed something really strange: the microscopic parasite appears to have no mitochondrial genome. Mitochondria, often referred to as the "energy base of the cell," are organelles that rely on oxygen for energy production.

At first, scientists at Tel Aviv University thought it was a mistake, so they re-analyzed and confirmed that the parasite had no mitochondrial genome, meaning it did not produce energy like all other animals know.

Although other single-celled organisms, such as amoeba and fungi, have also developed the ability to survive in anaerobic environments, no animal such as Henneguya salminicola qualifies as an organism despite having fewer than 10 cell.

This microscopic parasite does not appear to have a mitochondrial genome.

'It is often assumed that in the course of evolution, organisms became more and more complex, and that simple single-celled or less-celled organisms were the ancestors of complex organisms,' said Professor Dorothee Huchon, a wrote one of the authors of a study on Henneguya.

But here, right in front of our eyes, is an animal whose evolutionary process has reversed. Living in an oxygen-free environment, it removed unnecessary genes responsible for aerobic respiration and became an even simpler organism.

A distant relative to jellyfish, this tadpole-like parasite forms small white cysts in the flesh of salmon. It is possible that it does not harm fish and does not infect humans, the researchers said.

This environment is believed to be one of the possible causes of its mitochondria to disappear. Fish muscle is known to be a low-oxygen environment, so Henneguya salminicola may have simply adapted to generate its energy in some way.

What exactly powers the microscopic parasite instead of oxygen remains a mystery that scientists have yet to uncover.

Although microscopic images show that the mitochondrial-associated organelles retain some of the physical features of the original organ, they lack all the normal genetic information, which suggests that The parasite is no longer capable of standard aerobic respiration.

Some researchers believe that Henneguya salminicola may somehow be sucking energy from surrounding salmon cells, others say it may have the ability to breathe without oxygen. There are also some in the scientific community who argue that this organism can live a lifetime without oxygen.

Despite the controversy surrounding the parasite's ability to survive without oxygen, it is undeniable that its discovery has changed the way we view evolution.

'It confirms that adaptation to an anaerobic environment is not only present in unicellular eukaryotes, but also evolved in parasitic, multicellular animals,' the researchers note. idea.