The NRAMP family of metal-ion transporters

Biochim Biophys Acta. 2006 Jul;1763(7):609-20. doi: 10.1016/j.bbamcr.2006.05.007. Epub 2006 May 19.


The family of NRAMP metal ion transporters functions in diverse organisms from bacteria to human. NRAMP1 functions in metal transport across the phagosomal membrane of macrophages, and defective NRAMP1 causes sensitivity to several intracellular pathogens. DCT1 (NRAMP2) transport metal ions at the plasma membrane of cells of both the duodenum and in peripheral tissues, and defective DCT1 cause anemia. The driving force for the metal-ion transport is proton gradient (protonmotive force). In DCT1 the stoichiometry between metal ion and proton varied at different conditions due to a mechanistic proton slip. Though the metal ion transport by Smf1p, the yeast homolog of DCT1, is also a protonmotive force, a slippage of sodium ions was observed. The mechanism of the above phenomena could be explained by a combination between transporter and channel mechanisms.

Publication types

  • Review

MeSH terms

  • Amino Acid Sequence
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Cation Transport Proteins / chemistry
  • Cation Transport Proteins / metabolism*
  • Metals / metabolism*
  • Molecular Sequence Data


  • Carrier Proteins
  • Cation Transport Proteins
  • Metals
  • natural resistance-associated macrophage protein 1