Research into adaptations to extreme conditions in eukaryotic model organisms – fungi


In the framework of the IC Mycosmo, the Microbial Culture Collection Ex performs research into extremophilic microbial adaptations to life under hypersaline conditions, at extremely low temperatures, and under other stress factors. 


Climate change is burdening the environment with high concentrations of nanoparticles and extreme physico-chemical conditions (e.g., high or low temperatures, increased concentrations of salt, high hydrostatic pressures, extreme pH), thus creating extreme biospheres, which include (micro)organisms that have successfully adapted to life under extreme conditions. These (micro)organisms are known as extremophiles. They are interesting from the point of view of biodiversity, adaptation and potential biotechnological applications. Research into extremophilic microorganisms has intensified in Europe over the last 15 years. This research is performed at the level of the ecology of the extreme environments, as well as at the level of the investigation of extremophilic model microorganisms. These ecological levels have included the isolation, identification and description of potentially new species and their phylogenetic positioning, and population studies. Studies on the levels of model organisms include the biochemical, physiological and molecular mechanisms that enable life to continue under these extreme conditions. 


With the possibility of uniting basic and applied points of view, and also in terms of the ecology of such extreme environments that representing the few still unexplored niches on our planet, this type of research is interesting also for a broader audience and for the popularisation of science. 


Some of the oldest extreme environments on our planet are hypersaline environments, which are inhabited by halophilic microorganisms. Until the discovery of halophilic fungi in Sečovelje salterns in Slovenia, and later also in other hypersaline environments around the World, it was believed that only prokaryotic bacteria and archaea can inhabit such hypersaline environments. This research into halophilic fungi opened a new field of of investigations into eukaryotic extremophiles. As fungi are more closely related and similar to higher organisms than prokaryotes, the results of these studies have enabled the more direct use and transfer of basic knowledge into, for example, plants growing on salinised soil. Excess salinisation of the soil due to irrigation strongly threatens agronomy, in particular in the Mediterranean area, in Australia, Pakistan, Israel and California, USA, and represents a worrying production burden. The cheapest solution would be the cultivation of agronomically important crops in environemnts with increased salinity due to an increase in the endogenous resistance of the plants to salt (i.e., halotolerance) through transgenic procedures. Understanding of mechanisms that have enable adaptations to life under extreme conditions therefore helps with our understanding and solving of problems connected with human impact in the environment and with climate changes. 


Molecular research of adaptation into extreme conditions 


Within the framework of the IC Mycosmo, we carry out molecular research into eukaryotic extremophilic model organisms. Extremophilic microorganisms represent unique physiological and molecular models for research into adaptation to extreme conditions. For this purpose, different molecular techniques have been introduced, such as analysis of differentially expressed genes and construction of transgenic constructs. In 2010, our molecular research into adaptation lead to the first sequencing of the genomic information of a higher ranking organism (a yeast) in Slovenia; this was followed by the sequencing of five more yeast genomes in 2011. 


Investigation of extremophilic fungus genomes, and data and knowledge dissemination 


In the fields of genomics and transcriptomics, the IC Mycosmo represents an important centre that has unique knowledge in the field of halotolerant/ halophilic fungi. As well as being the first such centre on a national level, with the help of next-generation sequencing and with our genomic sequencing of eukaryotic microorganisms, the data obtained have a special special significance also on the global scale: the research of the IC Mycosmo made available the first genomic sequences obtained for any halophilic or extremely halotolerant fungi in the World. This information also has applied value, following the increasing efforts to improve stress tolerance in industrially important species (e.g., crops, industrial microorganisms), which represents an important contribution to solving problems in the agronomy and in biotechnology based economies.