First discovery of ‘anaerobic creatures’: Jellyfish-like parasites don’t breathe

Earlier this year, scientists discovered a jellyfish-like parasite that does not have a mitochondrial genome, the only multicellular creature known to do not have a mitochondrial genome, meaning the creature cannot breathe, according tomedia reports, because its survival is completely undependent on oxygen!

First discovery of 'anaerobic creatures': Jellyfish-like parasites don't breathe

Using deep sequencing and fluorescence microscopes, the researchers conducted an in-depth analysis of Henneguya salminicola and found that they had lost their mitochondrial genomes, in addition to the ability to breathe aerobically, and almost all of the nucleocore genes involved in transcribing and replicating mitochondria had been lost.

The discovery not only changed our understanding of how life on Earth lives, but could also be an important revelation for the search for extraterrestrial life.

Earth life began to develop aerobic metabolism about 1.45 billion years ago, larger paleobacteria can devour smaller bacteria, and then the bacteria will be planted in the germ, this symbiotic way is conducive to the survival of both sides.

This symbiotic relationship led to the evolution of two species, culminating in smaller bacteria in a cytometor called mitochondria, each of which has a large number of mitochondria in addition to red blood cells, which are necessary for the respiratory process. Mitochondria break down oxygen to produce a molecule called adenosine triphosphate, which multicellular organisms use to generate energy for cells.

We know that some evolutionary adaptations allow organisms to survive in low-oxygen environments, and that some single-celled organisms have evolved mitochondrial-related anaerobic metabolites, but the existence of single anaerobic multicellular organisms remains a hotly debated topic in the scientific community.

A team of researchers at Tel Aviv University in Israel studied a common salmon parasite and found that the parasite, known as Henneguya salminicola, was a stingy creature that belonged to corals, jellyfish and anemones. Although the cysts that the parasite sat in salmon are hard to see, they are harmless to salmon and co-exist with the salmon life cycle.

These tiny hedgehogs hidden in the host can survive with out-of-oxygen conditions, and it is difficult to reveal how they survived without a closer look at the creature’s DNA.

Using deep sequencing and fluorescence microscopes, the researchers conducted an in-depth analysis of Henneguya salminicola and found that they had lost their mitochondrial genomes, in addition to the ability to breathe aerobically, and almost all of the nucleocore genes involved in transcribing and replicating mitochondria had been lost.

Like single-celled organisms, it has evolved mitochondrial-related organelles, but they are unique in that folds are usually not visible on the inner membrane. Using relevant sequencing and microscope observation methods, the researchers looked at another parasitic parasitic parasite, Myxobolus squamalis, as a reference comparison to clearly show changes in the mitochondrial genome.

The results suggest that Henneguya salminicola is a multicellular organism that does not require oxygen to survive, but exactly how it survived remains a mystery, and that adenosine triphosphate may have been absorbed from the host, but the finding sits still needs to be verified.

But this loss of mitochondrial genomes is consistent with the general trend of such biological evolution, a process of genetic simplification that, over the years, has largely evolved from a free-living jellyfish ancestral species to a simpler parasite we see today.

They have lost most of the genomes of their ancient ancestors, but strangely, they retain a complex structure similar to jellyfish stingcells, not used to stab prey, but to cling to the host, thus satisfying the survival adaptation stoics that evolved from jellyfish to parasites. The parasite is very eye-like, and the discovery may help fisheries adjust their strategy to deal with parasites, and although the parasites are harmless to humans, no one wants to buy salmon with eye-shaped parasites.

The new study is important and helps scientists understand the mystery of biological survival, pointing out that adaptation to anaerobic environments is not unique to single-celleud eukaryotes, but evolved from multicellular parasites.

Henneguya Salminicola provides important clues to understanding the evolutionary shift of living things from aerobic metabolism to pure anaerobic metabolism, according to a study published recently in the Proceedings of the National Academy of Sciences.