Fungi play an important role in the ecosystem, cycling carbon and micronutrients and many even entering symbiotic relationships with plants. This can be of utmost importance for the optimization of plant growth, as research shows that mycorrhizal plants greatly benefit from the mycorrhiza due to a much larger root system and thus increased access to water and micronutrients and supposedly diminished stress from pathogens and heavy metal stress.
Our research group focuses on heavy metal speciation in the sporocarps and mycelia of ectomycorrhizal fungi. We are especially interested in the so called hyperaccumulators, i.e. fungal species that accumulate extraordinary amounts of heavy metals, sometimes even multiple elements at once. Hyperaccumulating taxons are first discovered by measuring the total amount of metals in sporocarps from pristine and polluted habitats acquired by our collaborator Jan Borovička. If a hyperaccumulating taxon is confirmed, further molecular and biochemical analyses are performed to elucidate the biochemical background of the metal speciation (metallothioneins, compartmentalization, novel metalloproteins) and then the genetic determinants responsible for the hyperaccumulating phenotype. Our collection comprises of over twenty hyperaccumulating fungal species in the form of mycelial explants, including Amanita, Hebeloma, and Agaricus sp. This gives us a unique opportunity to study the effects of heavy metal overload and poisoning on these organisms both in vitro and in vivo.
Our other collaborative projects include speciation and transformation of arsenic in arsenic hyperaccumulators and discovering novel fungal proteins and compounds with potential technological and medicinal importance.
Current projets
Speciation of cadmium, zinc and copper in sporocarps and mycelia of fungi of the species Russula, Hebeloma, Amanita muscaria, Cystoderma carcharias, Agaricus crocodilinus – besides classic biochemical approach for the identification of metal species, we are also relying on the available public genomic sequences in which we can reveal relevant protein sequences by bioinformatic analysis and then isolate the genes coding for these proteins by homology cloning or by construction of RACE and Genome walking libraries.
Identification of bacterial communities in sporocarps and in the mycosphere – although our main field of interest are metals in fungal sporocarps, and the genes and proteins related to metal metabolism, the question of why the metal hyperaccumulation trait has evolved in fungi has lead us to the study of microbial communities, so called microbiomes, by NGS methods. Our goal is to elucidate if the bacterial communities living in the proximity of sporocarps and mycelia are different from bacterial communities living at the same locality but without a contact with the fungus.
Preparation of chiral compounds by Cunninghamella elegans – this fungus is considered very interesting for the testing of the metabolism of toxic compounds, since the enyzmatic apparatus of the fungus is similar to that of animal hepatocytes. This can be used for the prediction of metabolites of new synthetic drugs or even production of novel bioactive compounds. Currently, we are cooperating with Dr. Michal Kohout, testing if the fungus is able to keep or change the chirality of the tested compounds.
Identification of novel aluminium complex in mycelia of Oidiodendron sp. – an isolate of an unknown species of this ericoid mycorrhizal fungus was brought to us from Poland. After metal tolerance screening, it was shown that the fungus is multitolerant to many metals, including aluminium. Currently we are investigating the form of aluminium stored within the cells, including using fluorescence microscopy with an aluminium probe, and transmission electron microscopy with energy dispersive spectroscopy to determine the exact place of the Al complexes within the fungal cells.
Identification of novel cadmium complexes in sporocarps of Agaricus crocodilinus – literature search revealed an interesting article from 1983, in which German scientists found a cadmium complex with high amounts of saccharides but no sulfur amino acids, which is strange, considering cadmium has been mostly found to bind with proteins containing sulfur. This complex was called “mycophosphatin” and our goal is to isolate it and describe its biochemical properties.
Isolation and characterization of biomolecules from sporocarps and mycelia of Amanita muscaria – this fungus belongs to mildly poisonous species. Its habitat extends over the whole northern hemisphere and besides being poisonous it has been known for being psychotropic, and thus it is used in traditional shaman rituals and as a recreational drug. In our collaboration with the BAFA lab, we are investigating the potential for novel medicinal use of A. muscaria.
Speciation of arsenic in the ink stain bolete, Cyanoboletus pulverulentus – this edible fungus was studied previously by our collaborators at Graz University in Austria. Their research yielded information about very high amounts of arsenic and potentially novel arsenic species. Our goal is to identify potential novel species and to study the metabolic pathways that lead to the formation of these species both in laboratory and in the environment. This project is done in collaboration with Department of Analytical Chemistry.