Under the influence of the drug fluconazole, the fungus Candida albicans can change its mode of reproduction and thus become even more resistant. Scientists at the University of Würzburg report this in the journal mBio.
The yeast Candida albicans occurs in most healthy people as a harmless colonizer in the digestive tract. However, it can also cause life-threatening infections, especially in immunocompromised patients.
Zwei mit Fluoreszenz markierte Zellen des Pilzes Candida albicans paaren sich. Zunächst entstehen Auswüchse, über die sie miteinander verschmelzen. Ersichtlich durch das Vermischen der roten und grünen Farbe.
Bild: Bernardo Ramírez-Zavala/Universität Würzburg
These infections are usually treated with the drug fluconazole, which inhibits the synthesis of ergosterol in Candida. Ergosterol fulfils similar important functions in fungi as cholesterol in humans.
Candida albicans can, however, become resistant to this drug. Scientists have uncovered the main mechanisms of fluconazole resistance in recent years.
The group of Professor Joachim Morschhäuser from the Institute for Molecular Infection Biology at Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany, has contributed important findings.
The fungus succeeds in becoming resistant with numerous mechanisms. For example, it uses pumps to transport the drug out of its cells. "Highly resistant Candida albicans, in which fluconazole therapy fails, usually use a combination of several of these mechanisms," says Morschhäuser.
New combinations of resistance mechanisms
Normally Candida albicans reproduces asexually by cell division. Morschhäuser's research group has now discovered that resistant fungal cells can quickly switch to sexual reproduction in the presence of fluconazole.
In this case, the cells fuse and unite their genetic material. In the offspring cells, different resistance mechanisms are newly combined and the fungal population thus becomes even less sensitive to fluconazole.
"In our investigations, we found out that the cells that retained the advantageous resistance characteristics are selected and become dominant in the population when treated with fluconazole," says first author Christina Popp.
Fluconazole not only selects for resistance mutations, but can also lead to changes in the genome that make the normally asexual fungus "mating-competent", thereby enabling the cells to combine individually acquired resistance mechanisms and produce highly resistant offspring.
Knowledge about the molecular mechanisms of drug resistance can be useful for the development of better and new drugs and help overcome resistance.
Morschhäuser assumes that the resistance mechanisms described here are only one example of how Candida albicans can change in its host. Next, his team wants to investigate whether other forms of adaptation can also contribute in a similar way to the successful establishment of the fungus in different host niches.
This research was funded by the German Research Foundation (DFG) and the Open Access Publication Programme of DFG and JMU.
Prof. Dr. Joachim Morschhäuser, Institute for Molecular Infection Biology, JMU, T +49 931 31-82152, firstname.lastname@example.org
Popp C, Ramírez-Zavala B, Schwanfelder S, Krüger I, Morschhäuser J (2019) Evolution of fluconazole-resistant Candida albicans strains by drug-induced mating competence and parasexual recombination. mBio 10:e02740-18. https://doi.org/10.1128/mBio.02740-18
Corinna Russow/Robert Emmerich | Julius-Maximilians-Universität Würzburg
Rising water temperatures could endanger the mating of many fish species
03.07.2020 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
Moss protein corrects genetic defects of other plants
03.07.2020 | Rheinische Friedrich-Wilhelms-Universität Bonn
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.
Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....
Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.
Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...
A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...
Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"
The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...
With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.
Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...
02.07.2020 | Event News
19.05.2020 | Event News
07.04.2020 | Event News
03.07.2020 | Life Sciences
03.07.2020 | Studies and Analyses
03.07.2020 | Power and Electrical Engineering