Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1128/jb.00080-24
Licence creative commons licence
Title (Primary) A flow equilibrium of zinc in cells of Cupriavidus metallidurans
Author Nies, D.H.; Schleuder, G.; Galea, D.; Herzberg, M. ORCID logo
Source Titel Journal of Bacteriology
Year 2024
Department EAC
Volume 206
Issue 5
Page From e00080-24
Language englisch
Topic T9 Healthy Planet
Supplements https://journals.asm.org/doi/suppl/10.1128/jb.00080-24/suppl_file/jb.00080-24-s0001.pdf
Keywords Cupriavidus metallidurans; zinc; zinc transport
Abstract The hypothesis was tested that a kinetical flow equilibrium of uptake and efflux reactions is responsible for balancing the cellular zinc content. The experiments were done with the metal-resistant bacterium Cupriavidus metallidurans. In pulse-chase experiments, the cells were loaded with radioactive 65Zn and chased with the 100-fold concentration of non-radioactive zinc chloride. In parallel, the cells were loaded with isotope-enriched stable 67Zn and chased with non-enriched zinc to differentiate between zinc pools in the cell. The experiments demonstrated the existence of a kinetical flow equilibrium, resulting in a constant turnover of cell-bound zinc ions. The absence of the metal-binding cytoplasmic components, polyphosphate and glutathione, metal uptake, and metal efflux systems influenced the flow equilibrium. The experiments also revealed that not all zinc uptake and efflux systems are known in C. metallidurans. Cultivation of the cells under zinc-replete, zinc-, and zinc-magnesium-starvation conditions influenced zinc import and export rates. Here, magnesium starvation had a stronger influence compared to zinc starvation. Other metal cations, especially cobalt, affected the cellular zinc pools and zinc export during the chase reaction. In summary, the experiments with 65Zn and 67Zn demonstrated a constant turnover of cell-bound zinc. This indicated that simultaneously occurring import and export reactions in combination with cytoplasmic metal-binding components resulted in a kinetical flow equilibrium that was responsible for the adjustment of the cellular zinc content.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=29079
Nies, D.H., Schleuder, G., Galea, D., Herzberg, M. (2024):
A flow equilibrium of zinc in cells of Cupriavidus metallidurans
J. Bacteriol. 206 (5), e00080-24 10.1128/jb.00080-24