Project description:Mesorhizobium metallidurans STM 2683 and Mesorhizobium sp. strain STM 4661 were isolated from nodules of the metallicolous legume Anthyllis vulneraria from distant mining spoils. They tolerate unusually high zinc and cadmium concentrations as compared to other mesorhizobia. This work aims to study the gene expression profiles associated with zinc or cadmium exposure and to identify genes involved in metal tolerance in these two metallicolous Mesorhizobium strains of interest for mine phytostabilization purposes. Mesorhizobium metallidurans STM 2683 and Mesorhizobium sp. strain STM 4661 with three treatments (control, Zn and Cd).
Project description:Mesorhizobium metallidurans STM 2683 and Mesorhizobium sp. strain STM 4661 were isolated from nodules of the metallicolous legume Anthyllis vulneraria from distant mining spoils. They tolerate unusually high zinc and cadmium concentrations as compared to other mesorhizobia. This work aims to study the gene expression profiles associated with zinc or cadmium exposure and to identify genes involved in metal tolerance in these two metallicolous Mesorhizobium strains of interest for mine phytostabilization purposes.
Project description:Zinc is a central player in the metalloproteomes of prokaryotes and eukaryotes. We used a top-down quantitative proteomic approach to reveal the repository of the zinc pools in the proteobacterium Cupriavidus metallidurans. About 60% of the theoretical proteome of C. metallidurans were identified, quantified, and compared between a ΔzupT mutant defect in zinc allocation and its parent strain. In both strains, the number of zinc-binding proteins and their binding sites exceeded that of the zinc ions per cell, indicating that the totality of the zinc proteome provides empty binding sites for incoming zinc ions. This zinc repository plays a central role in zinc homeostasis in C. metallidurans and probably also in other organisms.
