Eukaryotic cells iron uptake

Eubacterium 3, 6 Euglena 19 Euglenophyta 20 Eukaryote(s), unicellular 18-22 Eukaryotic cells 11-15 definition of 2 iron uptake 839 structure 10 Evolution 9... 

Fig. 7. Cartoon depicting the functional and epistatic relationship between copper and iron uptake and trafficking in yeast. The handling of iron hy eukaryotic cells is ultimately dependent on a copper ferroxidase. In yeast, either copper deficiency or loss of function in any of the copper-handling proteins indicated in the cartoon causes an iron deficiency that is correctable readily by extranutritional copper but not by iron. Loss of function in FetSp or Ftrlp, however, is correctable by neither metal ion.

Uptake of iron by eukaryotic cells 879 3. Cofactor F jq and Methyl-Coenzyme M... 

Eukaryotic phytoplankton do not appear to produce siderophores and there is little evidence for direct cellular uptake of ferric siderophore chelates. Instead there is mounting evidence for the utilization of a high-affinity transport system that accesses ferric complexes via their reduction at the cell surface and subsequent dissociation of the resulting ferrous-ligand complexes. The released ferrous ions bind to iron(ii) receptors on iron transport proteins located on the outer cell membrane, which transport the iron into the cell. This intracellular transport involves the reoxidation of bound iron(ii) to iron(iii) by a copper protein, and thus copper is required for cellular iron uptake. The availability of iron to this transport... 

The differences between prokaryotic and eukaryotic phytoplanktonic uptake of iron must affect competition and hence the composition of primary producer communities (Hutchins et al. 1999). The rate of transport of iron into cells depends upon the number of receptors on the membrane surface, so low iron concentrations favour growth of the pi-coplankton, which have a large surface area to volume ratio. 

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