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Structural and functional properties of a magnesium transporter of the SLC11/NRAMP family.

ABSTRACT: Members of the ubiquitous SLC11/NRAMP family catalyze the uptake of divalent transition metal ions into cells. They have evolved to efficiently select these trace elements from a large pool of Ca2+ and Mg2+, which are both orders of magnitude more abundant, and to concentrate them in the cytoplasm aided by the cotransport of H+ serving as energy source. In the present study, we have characterized a member of a distant clade of the family found in prokaryotes, termed NRMTs, that were proposed to function as transporters of Mg2+. The protein transports Mg2+ and Mn2+ but not Ca2+ by a mechanism that is not coupled to H+. Structures determined by cryo-EM and X-ray crystallography revealed a generally similar protein architecture compared to classical NRAMPs, with a restructured ion binding site whose increased volume provides suitable interactions with ions that likely have retained much of their hydration shell.

SUBMITTER: Ramanadane K

PROVIDER: S-EPMC8806188 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Structural and functional properties of a magnesium transporter of the SLC11/NRAMP family.

Ramanadane Karthik K Straub Monique S MS Dutzler Raimund R Manatschal Cristina C

eLife 20220110

Members of the ubiquitous SLC11/NRAMP family catalyze the uptake of divalent transition metal ions into cells. They have evolved to efficiently select these trace elements from a large pool of Ca2+ and Mg2+, which are both orders of magnitude more abundant, and to concentrate them in the cytoplasm aided by the cotransport of H+ serving as energy source. In the present study, we have characterized a member of a distant clade of the family found in prokaryotes, ter ...[more]

PMID: 35001872

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