Editor: Richard Staples
Extracellular and cellular mechanisms sustaining metal tolerance in ectomycorrhizal fungi
Article first published online: 15 DEC 2005
FEMS Microbiology Letters
Volume 254, Issue 2, pages 173–181, January 2006
How to Cite
Bellion, M., Courbot, M., Jacob, C., Blaudez, D. and Chalot, M. (2006), Extracellular and cellular mechanisms sustaining metal tolerance in ectomycorrhizal fungi. FEMS Microbiology Letters, 254: 173–181. doi: 10.1111/j.1574-6968.2005.00044.x
Present address: Christophe Jacob, IFR 111, UMR 7567 CNRS/UHP Maturation des ARN et Enzymologie Moléculaire, Université Henri Poincaré– Nancy I, Faculté des Sciences et Techniques BP239, F54506 Vandoeuvre-les-Nancy Cedex, France.
- Issue published online: 15 DEC 2005
- Article first published online: 15 DEC 2005
- Received 7 September 2005; revised 13 October 2005; accepted 13 October 2005.
- metal tolerance;
- ectomycorrhizal fungi;
- intracellular chelation;
- extracellular chelation;
- transport system
This review focuses on recent evidence that identifies potential extracellular and cellular mechanisms that may be involved in the tolerance of ectomycorrhizal fungi to excess metals in their environment. It appears likely that mechanisms described in the nonmycorrhizal fungal species are used in the ectomycorrhizal fungi as well. These include mechanisms that reduce uptake of metals into the cytosol by extracellular chelation through extruded ligands and binding onto cell-wall components. Intracellular chelation of metals in the cytosol by a range of ligands (glutathione, metallothioneins), or increased efflux from the cytosol out of the cell or into sequestering compartments are also key mechanisms conferring tolerance. Free-radical scavenging capacities through the activity of superoxide dismutase or production of glutathione add another line of defence against the toxic effect of metals.