Affiliation:
1. Moscow Lomonosov State University
2. A. N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences
3. Moscow Lomonosov State University; A. N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences
Abstract
Our analysis of metabolic and ecological features of fungi indicates a high bioremediation potential of fungal mycelium. The relevance of the problems solved in this work is conditioned by insufficiently studied mechanisms and conditions of micromycetal activity on heavy metal detoxication. The effect of copper on the development of two micromycete species, namely, melanised Alternaria alternata (Fr.) Keissl., 1912 and hyaline Fusarium oxysporum Schltdl., 1824 cultivated on Czapek agar (with 2 or 3% sucrose) was compared; the ability of mycelium to sorb copper cations when grown in a liquid culture with 0, 0.05, 0.1, 0.25, and 0.5 mg Cu2+ / L was evaluated. F. oxysporum had noticeable advantages in terms of growth rate, tolerance, conidia production on medium with Cu2+. The effective concentration of copper (EC50), indicating the resistance of the fungus, increased for F. oxysporum by 1.5 times with increasing sucrose content in the medium. The melanised culture of A. alternata was superior to F. oxysporum in terms of sorption capacity. The percentage of Cu2+ extraction by fungal mycelium from the medium reached 40% in the case of F. oxysporum and twice as much in the case of A. alternata . The vast majority of copper was sorbed by the cell walls of hyphae and washed away by water. A small amount (a maximum of 0.16 µg Cu2+ /g dry mycelium of A. alternate ) penetrated inside the mycelial cells. F. oxysporum, which had no intracellular protective melanins, accumulated Cu2+ (2 to 14 times) less. The results show that the mechanisms of resistance to Cu2+ and sorption are different in the studied species: in Fusarium they are determined mainly by the barrier functions of hyphae cell walls, while in Alternaria melanin plays a significant role in protection against Cu toxic action.
Publisher
A.N.Severtsov Institute of Ecology and Evolution RAS - IEE RAS
Reference17 articles.
1. Volkova V. D., Fedoseeva E. V., Terekhova V. A. Influence of metabolites micromycetes Alternaria alternata and Fusarium oxysporum on bacterial activity in the aquatic environment under copper pollution. In: Ecology of the Rivers Basins : Proceedings of the XI International Scientific Conference. Vladimir, Vladimir State University named after Alexander and Nikolay Stoletovs, 2023, pp. 316–320 (in Russian).
2. Nikolaeva O. V., Terekhova V. A. Improvement of laboratory phytotest for the ecological evaluation of soils. Eurasian Soil Science, 2017, vol. 50, no. 9, pp. 1105–1114. https://doi.org/10.1134/S1064229317090058
3. Skugoreva S. G., Kantor G. Ya., Domracheva L. I. Biosorption of heavy metals by micromycetes: Specificity of the process, mechanisms, kinetics. Theoretical and Applied Ecology, 2019 a, no. 2, pp. 14–31 (in Russian). https://doi.org/10.25750/1995-4301-2019-2-014-031
4. Skugorev а S. G., Kantor G. Ya., Domracheva L. I., Sheshegova T. K. Assessment of sorption abilities of various species of Fusarium micromycetes in relation to heavy metal ions. Theoretical and Applied Ecology, 2019 b, no. 4, pp. 102–109 (in Russian). https://doi.org/10.25750/1995-4301-2019-4-103-109
5. Solopov M. V., Legenkiy Yu. A., Bespalova S. V., Holyavka M. G. Biosorption of heavy metals ions by yeast cells modified with magnetite nanoparticles. Proceedings of Voronezh State University. Series: Chemistry. Biology. Pharmacy, 2019, no. 1, pp. 96–102 (in Russian).