Metabolomics of the recovery of the filamentous fungus Cunninghamella echinulata exposed to tributyltin

The exposure of microorganisms to toxic compounds induces a range of responses at different levels of the cell morphology, biochemistry and physiology. Tributyltin (TBT) is a highly toxic compound used for many years in industry as a marine anti-fouling agent or as a biocide in preservatives of wood. We previously described a microscopic filamentous fungus Cunninghamella echinulata IM 2611 capable of efficient degradation of TBT at a high concentration. Additionally, we demonstrated that TBT showed a negative effect on fungal growth, as well as protein and amino acid profiles. This study used microscopic, metabolic and targeted metabolomic analyses for a better understanding of the processes occurring in the fungal hyphae of C. echinulata during exposure to highly toxic TBT. The exposure to TBT strongly inhibited the metabolic activity of C. echinulata, leading to changes in the hyphal structure. In addition, the study showed disturbances in the functioning of the major biochemical pathways in the cells through changes in the profile of metabolites belonging to glycolysis, tricarboxylic acid (TCA) cycle, amino acids and nucleotides pathways. Despite many adverse changes, the fungus was able to recover in the toxic environment.