Copper stress and filamentous fungusHumicola lutea103 — ultrastructural changes and activities of key metabolic enzymes
Tóm tắt
Humicola lutea 103 is a copper-tolerant fungal strain able to grow in the presence of 300 μg·mL–1Cu2+under submerged cultivation. To prevent the consequences of copper overload, microorganisms have evolved molecular mechanisms that regulate its uptake, intracellular traffic, storage, and efflux. In spite of this avoidance strategy, high heavy-metal concentrations caused distinct and widespread ultrastructural alterations in H. lutea. The mitochondria were the first and main target of the toxic action. The effect of copper on activities of the key enzymes (hexokinase, glucose-6-phosphate dehydrogenase, malate dehydrogenase, and isocitrate dehydrogenase) included in the 3 main metabolic pathways, glycolysis, pentose phosphate pathway, and tricarboxylic acid cycle, was investigated. High metal concentrations exhibited a dramatic negative effect on hexokinase, while the other 3 enzymes showed a significant and dose-dependent stimulation. On the basis of the present and previous results we concluded that the copper-induced oxidative stress plays an important role in the fungal tolerance to high Cu2+concentrations.
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Al Abboud M.A., 2011, Aust. J. Basic Appl. Sci., 5, 283
Baldrain, P. 2010. Effect of heavy metal on saprotrophic soil fungi.InSoil heavy metals.Edited byIrena Sherameti and Ajit Varma. Springer-Verlag, Berlin, Germany. pp. 263–280.
Belozerskaya, T., Aslanidi, K., Ivanova, A., Gessler, N., Egorova, A., Karpenko, Yu., and Olishevskaya, S. 2010. Characteristics of extremophylic fungi from chernobyl nuclear power plant. Vol. 1.InCurrent research, technology and education topics in applied microbiology and microbial biotechnology. Microbiology Series No. 2.Edited byA. Méndez-Vilas. Formatex, Badajoz, Spain. pp. 88–94.
Bergmeyer, H.U., and Moellering, H. 1983. Glucose-6-phosphate dehydrogenase.InMethods of enzymatic analysis. Vol. 3. Oxidoreductases, Transferases. 3rd ed.Edited byD.W. Moss. Verlag Chemie, Weinheim, Germany. pp. 191–197.
Bergmeyer, H.U., Graßl, M., and Walter, H.E. 1983. Hexokinase. In Methods of enzymatic analysis. Vol. 2. Samples, reagents, assessment of results. 3rd ed.Edited byH.U. Bergmeyer. Verlag Chemie, Weinheim, Germany. pp. 222–223.
Bridžiuvienė D., 2007, Biologija (Vilnius), 53, 54
Crichton, R.R. 2012. Metal assimilation pathways biological inorganic chemistry: a new introduction to molecular structure and function. 2nd ed. Elsevier B.V., Amsterdam, Netherlands. pp. 133–154.
Hefnawy M.A., 2009, Aust. J. Basic Appl. Sci., 3, 3158
Hirt R.R., 1949, Phytopathologist, 39, 31
Lee, J., Adle, D., and Kim, H. 2006. Molecular mechanisms of copper homeostasis in yeast.InMolecular biology of metal homeostasis and detoxification: from microbes to man.Edited byM.J. Tamás and E. Martinoia. Springer-Verlag, Berlin, Germany. pp. 1–37.
Quinn, J. 2008. Differences in stress responses between model and pathogenic fungi.InStress in yeasts and filamentous fungi.Edited bySimon Avery, M. Stratford, and P. Van West. Academic Press, London, UK. pp. 67–86.
Shafirovich, V., and Geacintov, N.E. 2010. Role of free radical reactions in the formation of DNA damage.InThe chemical biology of DNA damage.Edited byN.E. Geacintov and S. Broyde. WILEY-VCH Verlag GmbH&Co. KGaA, Berlin, Germany. pp. 81–104.
Shanker, A.K. 2008. Mode of action and toxicity of trace elements.InTrace elements as contaminants and nutrients: consequences in ecosystems and human health.Edited byM.N.V. Prasad. John Wiley & Sons, Inc., Hoboken, N.J., USA. pp. 523–554.
Smith, A.F. 1983. Malate dehydrogenase. Vol. 3. Oxidoreductases, Transferases. 3rd ed.InMethods of enzymatic analysis.Edited byH.U. Bergmeyer and M. Grassl Verlag Chemie, Weinheim, Germany. pp. 163–171.
Thannickal V.J., 2000, Am. J. Physiol. Lung Cell. Mol. Physiol., 279, L1005, 10.1152/ajplung.2000.279.6.L1005
Wang, S., Teng, S., and Fan, M. 2010. Interaction between heavy metals and aerobic granular sludge.InEnvironmental management.Edited bySantosh Kumar Sarkar. Sciyo, Croatia. pp. 173–188.