
Michiel Op de Beeck
Researcher

Zinc export results in adaptive zinc tolerance in the ectomycorrhizal basidiomycete Suillus bovinus
Author
Summary, in English
On Zn-polluted soils, populations of the ectomycorrhizal basidiomycete Suillus bovinus exhibit an elevated Zn tolerance when compared to populations on non-polluted sites. To elucidate the mechanism of Zn tolerance, the time-course of Zn uptake was studied in isolates with contrasting Zn tolerance. Unidirectional fluxes and subcellular compartmentation of Zn were investigated through radiotracer flux analyses. Fluorescence imaging was used to support the subcellular Zn compartmentation. After 2 h of exposure to 200 μM Zn, significantly more Zn was accumulated in Zn-sensitive isolates compared to tolerant isolates, despite similar short-term uptake kinetics and similar extracellular Zn sequestration in cell walls. In Zn-sensitive isolates twice as much Zn accumulated in the cytoplasm and 12 times more Zn in the vacuole. (65)Zn efflux analyses revealed a considerably faster Zn export in the Zn-tolerant isolate. The adaptive Zn tolerance in S. bovinus is therefore achieved by a preferential removal of Zn out of the cytoplasm, back into the apoplast, instead of the usual transfer of Zn into the vacuole. Zn exclusion in the fungal symbiont eventually contributes to a lower Zn influx in host plants.
Publishing year
2013-09
Language
English
Pages
33-1225
Publication/Series
Metallomics
Volume
5
Issue
9
Document type
Journal article
Publisher
Royal Society of Chemistry
Topic
- Microbiology
- Environmental Sciences
Keywords
- Adaptation, Physiological
- Basidiomycota/metabolism
- Biological Transport/drug effects
- Carbonyl Cyanide m-Chlorophenyl Hydrazone/pharmacology
- Cell Wall/metabolism
- Cytoplasm/metabolism
- Kinetics
- Mycelium/metabolism
- Mycorrhizae/metabolism
- Proton Ionophores/pharmacology
- Soil Pollutants/metabolism
- Vacuoles/metabolism
- Zinc/metabolism
Status
Published
ISBN/ISSN/Other
- ISSN: 1756-5901