Endofungal bacteria and the early response to climate change

Climate change impacts our daily life with heat waves, flooding and considerable destructions of infrastructure and natural environments. However, increasing temperatures also influence the physiology of microbes and their adaptation to habitats. Forests are among the most important habitats considering carbon cycling, CO2 production and hence climate change. With EndoFunClimate we tackle the early reaction of endofungal bacteria to elevated temperature as caused by climate change. These bacteria live within fungi and consequently bacteria and fungi share part of their metabolism. Currently, it is not well known how these partners interact with each other and how they react to environmental changes individually and/or together. Every adaptation to altered conditions starts with changes in gene regulation. Therefore we will analyze the genomes of microbial inhabitants of forest litter layers along with their gene regulation upon elevation of temperature. We will apply deep sequencing to enable construction of whole microbial genomes, even of so far unknown organisms. Additionally we will isolate fungi and check for the presence and identity of endofungal bacteria. From selected fungi we will isolate their bacteria and remove them from the fungus to test the contribution of these bacteria to the metabolism of the fungus and the reaction to elevated temperature. Considering propagation and evolution, sexual development of fungi contributes to adaptation to altered environmental conditions caused by a changing climate. For many fungi, successful mating depends on appropriate temperatures, for example around 22 C for the filamentous fungus Trichoderma reesei. Additionally, in some cases, endohyphal bacteria play a role. Hence we will also investigate the interplay of bacteria and their fungal hosts upon rising temperature to evaluate if and how sexual development of fungi may be affected by their internal bacteria and their reaction to climate change. In summary, this project shall elucidate the interaction between bacteria living in fungi with their fungal hosts at the molecular level and how this relationship changes if temperatures rise. We will gain information on the very early processes in these microbes, which determine whether they succeed or fail in adaptation to a warmer environment and we will analyze if their propagation may be affected by warming. Thereby, this project will contribute to a better understanding of the microbial contributions to litter degradation, the carbon cycle and climate change. Moreover, the knowledge created from EndoFunClimate will help to design beneficial fungus-(endohyphal) bacteria combinations for use in biological control of plant pathogens and reveal a treasure trove of novel enzyme sequences or gene clusters for production of potentially novel secondary metabolites useful for pharmaceuticals or industrial processes such as degradation of (micro-)plastics.