Iron transport siderophores

In times of iron deficiency, many bacteria and fungi release low molecular weight chelators called siderophores (see Iron Transport Siderophores). These molecules bind ferric iron tightly and the ferric-siderophore complexes are then transported into the cell by a system of uptake proteins. The first stage in the uptake process involves an outer membrane receptor specific to each siderophore. One of the best characterized of these receptors is FhuA, the ferrichrome uptake receptor of E. coli, and we will describe this in detail. However, though other ferric-siderophore complexes are taken up by cells, and their iron released by systems similar to those of ferrichrome, their mechanisms may vary from those of ferrichrome in some respects. FepA and FecA" are two of the outer membrane ferric-siderophore receptors that have recently been structurally characterized. 

Biomineralization Iron Heme Proteins Dioxygen Transport Storage Iron Heme Proteins Electron Transport Iron Heme Proteins, Mono- Dioxygenases Iron Heme Proteins, Peroxidases, Catalases Catalase-peroxidases Iron Inorganic Coordination Chemistry Iron Proteins with Dinuclear Active Sites Iron Proteins with Mononuclear Active Sites Iron-Sulfur Proteins Iron Transport Siderophores Metal Ion Toxicity. 

Analogs Iron Transport Siderophores Metallochaperones Metal Ion Homeostasis Zinc DNA-binding Proteins. 

Conventional treatments for hemochromatosis and for nutritional iron overload include reduction of dietary iron and periodic removal of blood (phlebotomy) until iron stores are reduced. In transfusion siderosis, it is necessary to eliminate iron via the urine by the intravenous infusion of highly specific chelating agents such as desferral (see Iron Transport Siderophores). This process is painful, laborious, and costly. The development of new orally effective iron chelators is expected. 

Dioxygen Related Ligands Iron Transport Siderophores Macrocyclic Ligands Oxides Solid-state Chemistry Oxygen Inorganic Chemistry Polyoxometalates Sol Gel Synthesis of Solids. 

E. coli Fur and homologs in other prokaryotes regulate the transcription of genes required for iron acquisition, including a host of distinct iron scavenging systems as well as the enzymes for siderophore biosynthesis see Iron Transport Siderophores, Metalloregulation). In addition,... 

Iron Transport Siderophores Metal Ion Toxicity Metal-related Diseases of Genetic Origin Metallochaperones Metal Ion Homeostasis MetaUoregulation Metallothioneins ... 

Ga-citrate is also commonly used for imaging infection and inflammation. " At sites of inflammation, the gallium-transferrin complex leaks into the extracellular space and Ga is transchelated from transferrin in blood to lactoferrin and siderophores see Iron Transport Siderophores), which are released by leukocytes and bacteria. Imaging with Ga takes place usually 24-72h following injection. 

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