Researchers discover unique non-oxygen breathing animal
Researchers at Tel Aviv University (TAU) have discovered a non-oxygen breathing animal. The unexpected finding changes one of science's assumptions about the animal world. A study on the finding was published on February 25 in PNAS by TAU researchers led by Prof. Dorothee Huchon of the School of Zoology at TAU's Faculty of Life Sciences and Steinhardt Museum of Natural History. The tiny, less than 10-celled parasite Henneguya salminicola lives in the salmon muscle. As it evolved, the animal, which is a myxozoan relative of jellyfish and corals, gave up breathing and consuming oxygen to produce energy.
"Aerobic respiration was thought to be ubiquitous in animals, but now we confirmed that this is not the case," Prof. Huchon explains. "Our discovery shows that evolution can go in strange directions. Aerobic respiration is a major source of energy, and yet we found an animal that gave up this critical pathway."
Some other organisms like fungi, amoebas or ciliate lineages in anaerobic environments have lost the ability to breathe over time. The new study demonstrates that the same can happen to an animal -- possibly because the parasite happens to live in an anaerobic environment.
Its genome was sequenced, along with those of other myxozoan fish parasites, as part of research supported by the U.S.-Israel Binational Science Foundation and conducted with Prof. Paulyn Cartwright of the University of Kansas, and Prof. Jerri Bartholomew and Dr. Stephen Atkinson of Oregon State University.
The parasite's anaerobic nature was an accidental discovery. While assembling the Henneguya genome, Prof. Huchon found that it did not include a mitochondrial genome. The mitochondria is the powerhouse of the cell where oxygen is captured to make energy, so its absence indicated that the animal was not breathing oxygen.
(Content Courtesy: https://www.eurekalert.org/pub_releases/2020-02/afot-tau022520.php)