Single-celled parasites of the genus Spironucleus are known to produce serious illness in farmed and aquarium fish.
In farmed salmon, these parasites create foul-smelling, puss-filled abscesses in muscles and internal organs. After the first outbreaks of this disease were described in farmed salmon in the late 1980’s, it was assumed that the cause was Spironucleus barkhanus, which is a fairly common parasite in the intestine of wild grayling and Arctic char.
In these fish species, however, the parasite is benign. For his doctorate, Jørgensen completed genetic studies showing that the disease-causing parasite in farmed salmon is genetically quite different from the species one finds in wild salmonids, although they appear to be identical, even under high magnification in an electron microscope. Based on this observation, the parasite that causes disease in farmed salmon has now been described as a new species – Spironucleus salmonicida.
“Our work has shown that genetic methods need to be utilised for correct identification of single-celled parasites of the genus Spironucleus. Parasites that appear to be identical morphologically may in fact be significantly different genetically. An exact identification of organisms that produce disease is extremely important in the fight to find the cause of disease outbreaks and provides an important contribution to finding appropriate diagnostic methods”, says Anders Jørgensen.
Jørgensen carried out similar studies with other Spironucleus species, which he also incorporatd into his doctoral thesis. Spironucleus vortens, which causes disease in aquarium fish, is also found in wild carp in Norway. Even though these parasites appear to be identical, they are very different genetically. Jørgensen also addressed the cod parasite Spironucleus torosus, which is found in several genetic variants. Based on these new findings, Jørgensen discusses whether the genetic differences between the variants provides a basis for splitting them into separate species.
Finally, Jørgensen investigated relationships between a series of species. These investigations showed that parasites from other Spironucleus families form three primary groups, which reflect the different environments their host species live in. His thesis hints that each of these groups may constitute a separate genus.
Magnhild Jenssen | alfa
Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences