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Updated: Jul 17, 2026
10:34
Essential Metal Uptake in Gram-negative Bacteria: X-ray Fluorescence, Radioisotopes, and Cell Fractionation
Published on: February 1, 2018
Recent progress in structure-function analyses of Nramp proton-dependent metal-ion transporters
P Courville1, R Chaloupka, M F M Cellier
1Institut National de la Recherche Scientifique, INRS-Institut Armand-Frappier, 531, Bd. des prairies, Laval, QC H7V 1B7, Canada.
Biochemistry and Cell Biology = Biochimie Et Biologie Cellulaire
|January 12, 2007
Summary
The Nramp (SLC11) family transports divalent metal ions, impacting iron and immune diseases. Key transmembrane segments 1 and 6 are crucial for metal-proton transport, aiding understanding of Nramp function and homeostasis.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- The Nramp (SLC11) family comprises proton-coupled transporters essential for cellular divalent metal ion (Me2+) absorption, including Mn2+, Fe2+, Co2+, and Cd2+.
- Conserved across eukaryotes and bacteria, Nramp homologs play critical roles in human health, with genetic variations linked to iron disorders and immune diseases.
Purpose of the Study:
- To elucidate the structure-function relationships of Nramp transporters, focusing on their transmembrane organization and the mechanism of metal-proton transport.
- To identify key structural components involved in the symport of divalent metal ions and protons.
Main Methods:
- Utilized functional complementation in yeast knockout strains.
- Performed electrophysiology analyses in Xenopus oocytes.
- Conducted transport assays in mammalian and bacterial cells, alongside direct and indirect measurements of SLC11 transporter properties.
Main Results:
- Identified transmembrane segments 1 (TMS1) and 6 (TMS6) as crucial for the symport of Me2+ and H+.
- Revealed insights into the overall transmembrane organization of Nramp transporters.
- Characterized the unusual mechanism coupling Me2+ and proton (H+) transport.
Conclusions:
- Transmembrane segments 1 and 6 are vital for Nramp-mediated divalent metal ion and proton symport.
- These findings advance the understanding of the Nramp transport mechanism.
- The study contributes to comprehending the role of Nramp transporters in Me2+ homeostasis and associated human diseases.
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