Storage and Homeostasis in Bacteria

Metal Transport, Storage, and Homeostasis in Plants and Fungi 

Biol( cal Inoi anic Chemistry, 2nd Edition. DOI 10.1016/B978-0-444-53782-9.00008-5. Copyright 2012 Elsevia- B.V. All rights reserved. 

FIGURE 8.1 (a) Structural organisation of a ferritin protein (From Yfatt, Hilton, Graff, 2010. Reproduced with permission from Elsevier), 

Iron is stored in these proteins in the ferric form, but is taken up as Fe +, which is oxidised by ferroxidase sites (a more detailed account of iron incorporation into ferritins is given in Chapter 19). As we point out in Chapter 13, ferritins are members of the much larger di-iron protein family. After oxidation, the Fe migrates to the interior cavity of the protein to form an amorphous ferric phosphate core. Whereas the ferritins in bacteria appear to fulfil the classical role of iron storage proteins, the physiological role of bacterioferritins is less clear. In Escherichia coli, it seems unlikely that bacterioferritin plays a major role in iron storage. 

FIGURE 8.2 Schematic representation of Fur-mediated gene expression. (Adapted from Andrews et al, 2003.) 

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