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Record Information
StatusDetected and Quantified
Creation Date2006-08-16 12:15:16 UTC
Update Date2017-12-20 20:33:20 UTC
Secondary Accession Numbers
  • HMDB00692
Metabolite Identification
Common NameFe2+
DescriptionIron is a chemical element with the symbol Fe and atomic number 26. Iron makes up 5% of the Earth's crust and is second in abundance to aluminium among the metals and fourth in abundance among the elements. Physiologically, it. exists as an ion in the body. Iron (as Fe2+, ferrous ion) is a necessary trace element used by all known living organisms. Iron-containing enzymes, usually containing heme prosthetic groups, participate in catalysis of oxidation reactions in biology, and in transport of a number of soluble gases. Iron is an essential constituent of hemoglobin, cytochrome, and other components of respiratory enzyme systems. Its chief functions are in the transport of oxygen to tissue (hemoglobin) and in cellular oxidation mechanisms. Inorganic iron involved in redox reactions is also found in the iron-sulfur clusters of many enzymes, such as nitrogenase (involved in the synthesis of ammonia from nitrogen and hydrogen) and hydrogenase. A class of non-heme iron proteins is responsible for a wide range of functions such as ribonucleotide reductase (reduces ribose to deoxyribose; DNA biosynthesis) and purple acid phosphatase (hydrolysis of phosphate esters). When the body is fighting a bacterial infection, the body sequesters iron inside of cells (mostly stored in the storage molecule ferritin) so that it cannot be used by bacteria. Depletion of iron stores may result in iron-deficiency anemia. Iron is used to build up the blood in anemia. Humans experience iron toxicity above 20 milligrams of iron for every kilogram of weight, and 60 milligrams per kilogram is a lethal dose. Over-consumption of iron, often the result of children eating large quantities of ferrous sulfate tablets intended for adult consumption, is the most common toxicological cause of death in children under six. The DRI lists the Tolerable Upper Intake Level (UL) for adults as 45 mg/day. For children under fourteen years old the UL is 40 mg/day. Iron is a metal extracted from iron ore, and is almost never found in the free elemental state.
FE (II) ionChEBI
Ferrous ionChEBI
Iron ion(2+)ChEBI
armco IronHMDB
Carbonyl ironHMDB
Ferrovac eHMDB
Malleable ironHMDB
Suy-b 2HMDB
Wrought ironHMDB
Chemical FormulaFe
Average Molecular Weight55.845
Monoisotopic Molecular Weight55.934942133
IUPAC Nameλ²-iron(2+) ion
Traditional Nameλ²-iron(2+) ion
CAS Registry Number15438-31-0
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of chemical entities known as homogeneous transition metal compounds. These are inorganic compounds containing only metal atoms,with the largest atom being a transition metal atom.
KingdomChemical entities
Super ClassInorganic compounds
ClassHomogeneous metal compounds
Sub ClassHomogeneous transition metal compounds
Direct ParentHomogeneous transition metal compounds
Alternative ParentsNot Available
  • Homogeneous transition metal
Molecular FrameworkNot Available
External Descriptors
Physiological effect

Health effect:

  Health condition:


Biological Location:


  Biofluid and excreta:

  Organ and components:

  Cell and elements:



Naturally occurring process:

  Biological process:

    Biochemical pathway:


Industrial application:

Biological role:

Physical Properties
Experimental Properties
Melting Point1538 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Physiological Charge2ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area0 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity0 m³·mol⁻¹ChemAxon
Polarizability1.78 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0a4i-9000000000-af3e7aec4f5bd9668683View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0a4i-9000000000-af3e7aec4f5bd9668683View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a4i-9000000000-af3e7aec4f5bd9668683View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0udi-9000000000-3335fec4c3184739b75eView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0udi-9000000000-3335fec4c3184739b75eView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0udi-9000000000-3335fec4c3184739b75eView in MoNA
Biological Properties
Cellular Locations
  • Extracellular
  • Mitochondria
Biofluid Locations
  • Blood
  • Cerebrospinal Fluid (CSF)
  • Saliva
  • Urine
Tissue Location
  • Brain
  • Liver
Acute Intermittent PorphyriaPw000174Pw000174 greyscalePw000174 simpleNot Available
Aromatic L-Aminoacid Decarboxylase DeficiencyPw000090Pw000090 greyscalePw000090 simpleNot Available
Beta Ureidopropionase DeficiencyPw000187Pw000187 greyscalePw000187 simpleNot Available
Beta-mercaptolactate-cysteine disulfiduriaPw000475Pw000475 greyscalePw000475 simpleNot Available
Carnitine SynthesisPw000016Pw000016 greyscalePw000016 simpleNot Available
Normal Concentrations
BloodDetected and Quantified9766 +/- 1246 uMAdult (>18 years old)Both
BloodDetected and Quantified8050.0 (7500.0-8600.0) uMAdult (>18 years old)Female
    • Geigy Scientific ...
BloodDetected and Quantified8950.0 (7900.0-10000.0) uMAdult (>18 years old)Male
    • Geigy Scientific ...
Cerebrospinal Fluid (CSF)Detected and Quantified3.6 +/- 3.6 uMElderly (>65 years old)BothNormal details
Cerebrospinal Fluid (CSF)Detected and Quantified9.293 +/- 1.140 uMAdult (>18 years old)Not SpecifiedNormal details
Cerebrospinal Fluid (CSF)Detected and Quantified0.8 (0.3-0.5) uMAdult (>18 years old)BothNormal
    • Geigy Scientific ...
Cerebrospinal Fluid (CSF)Detected and Quantified0.783 +/- 0.551 uMAdult (>18 years old)FemaleNormal details
SalivaDetected and Quantified5.918 +/- 2.530 uMAdult (>18 years old)BothNormal
    • Zerihun T. Dame, ...
SalivaDetected and Quantified0.448-2.865 uMChildren (1-13 years old)BothNormal
    • Gian Paolo Sighin...
SalivaDetected and Quantified84.699 +/- 47.274 uMAdult (>18 years old)Male
SalivaDetected and Quantified80.759 +/- 38.141 uMAdult (>18 years old)Male
SalivaDetected and Quantified13286.776 +/- 7288.0294 uMChildren (1-13 years old)Both
SalivaDetected and Quantified18.605 +/- 1.726 uMChildren (1-13 years old)Not SpecifiedNormal details
SalivaDetected and Quantified5.551 +/- 1.253 uMAdult (>18 years old)Not SpecifiedNormal
    • Natheer H. Al-Raw...
UrineDetected and Quantified0.0890 (0.0025-0.4579) umol/mmol creatinineAdult (>18 years old)Both
UrineDetected and Quantified0.11 (0.0-0.14) umol/mmol creatinineAdult (>18 years old)BothNormal
    • Geigy Scientific ...
    • West Cadwell, N.J...
    • Basel, Switzerlan...
UrineDetected and Quantified0.029 (0.014-0.053) umol/mmol creatinineAdult (>18 years old)MaleNormal
    • Geigy Scientific ...
    • West Cadwell, N.J...
    • Basel, Switzerlan...
Abnormal Concentrations
BloodDetected and Quantified8631 +/- 1497 uMAdult (>18 years old)Both
Multiple sclerosis
BloodDetected and Quantified20.1 +/- 7.7 uMAdult (>18 years old)BothParkinson's disease details
BloodDetected and Quantified16.3 +/- 7.7 uMElderly (>65 years old)BothAlzheimer's disease details
Cerebrospinal Fluid (CSF)Detected and Quantified0.488 +/- 0.374 uMAdult (>18 years old)Not Specifiedfibromyalgia details
Cerebrospinal Fluid (CSF)Detected and Quantified1.8 +/- 1.8 uMElderly (>65 years old)BothAlzheimer's disease details
Cerebrospinal Fluid (CSF)Detected and Quantified2.5 +/- 1.8 uMElderly (>65 years old)Not SpecifiedAlzheimer's disease details
SalivaDetected and Quantified45303.966 +/- 16295.103 uMChildren (1-13 years old)Both
Thalassemia Major
SalivaDetected and Quantified26877.966 +/- 10940.997 uMChildren (1-13 years old)Both
Thalassemia intermedia
SalivaDetected and Quantified18103.680 +/- 7370.400 uMAdolescent (13-18 years old)Both
Thalassemia Trait
SalivaDetected and Quantified4405.0497 +/- 1790.671 uMChildren (1-13 years old)Both
Iron Deficiency
SalivaDetected and Quantified24.008 +/- 6.984 uMChildren (1-13 years old)Not SpecifiedIron Deficiency details
SalivaDetected and Quantified33.172 +/- 8.529 uMChildren (1-13 years old)Not SpecifiedThalassemia Major details
SalivaDetected and Quantified40.971 +/- 9.292 uMChildren (1-13 years old)Not SpecifiedAplastic anemia details
SalivaDetected and Quantified2.507 +/- 0.537 uMAdult (>18 years old)Not SpecifiedOral squamous cell carcinoma
    • Natheer H. Al-Raw...
SalivaDetected and Quantified2.686 +/- 1.253 uMAdult (>18 years old)Not Specified
Oral squamous cell carcinoma
    • Natheer H. Al-Raw...
SalivaDetected and Quantified3.402 +/- 0.537 uMAdult (>18 years old)Not Specified
Oral squamous cell carcinoma
    • Natheer H. Al-Raw...
Associated Disorders and Diseases
Disease References
Alzheimer's disease
  1. Molina JA, Jimenez-Jimenez FJ, Aguilar MV, Meseguer I, Mateos-Vega CJ, Gonzalez-Munoz MJ, de Bustos F, Porta J, Orti-Pareja M, Zurdo M, Barrios E, Martinez-Para MC: Cerebrospinal fluid levels of transition metals in patients with Alzheimer's disease. J Neural Transm (Vienna). 1998;105(4-5):479-88. [PubMed:9720975 ]
  2. Bocca B, Forte G, Petrucci F, Pino A, Marchione F, Bomboi G, Senofonte O, Giubilei F, Alimonti A: Monitoring of chemical elements and oxidative damage in patients affected by Alzheimer's disease. Ann Ist Super Sanita. 2005;41(2):197-203. [PubMed:16244393 ]
Multiple sclerosis
  1. Forte G, Visconti A, Santucci S, Ghazaryan A, Figa-Talamanca L, Cannoni S, Bocca B, Pino A, Violante N, Alimonti A, Salvetti M, Ristori G: Quantification of chemical elements in blood of patients affected by multiple sclerosis. Ann Ist Super Sanita. 2005;41(2):213-6. [PubMed:16244395 ]
Parkinson's disease
  1. Forte G, Alimonti A, Pino A, Stanzione P, Brescianini S, Brusa L, Sancesario G, Violante N, Bocca B: Metals and oxidative stress in patients with Parkinson's disease. Ann Ist Super Sanita. 2005;41(2):189-95. [PubMed:16244392 ]
Associated OMIM IDs
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDFDB016251
KNApSAcK IDNot Available
Chemspider ID25394
KEGG Compound IDC14818
BioCyc IDFerric-Hydroxamate-Complexes
BiGG ID33552
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem Compound27284
ChEBI ID29033
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Gal S, Fridkin M, Amit T, Zheng H, Youdim MB: M30, a novel multifunctional neuroprotective drug with potent iron chelating and brain selective monoamine oxidase-ab inhibitory activity for Parkinson's disease. J Neural Transm Suppl. 2006;(70):447-56. [PubMed:17017567 ]
  2. Piga A, Galanello R, Forni GL, Cappellini MD, Origa R, Zappu A, Donato G, Bordone E, Lavagetto A, Zanaboni L, Sechaud R, Hewson N, Ford JM, Opitz H, Alberti D: Randomized phase II trial of deferasirox (Exjade, ICL670), a once-daily, orally-administered iron chelator, in comparison to deferoxamine in thalassemia patients with transfusional iron overload. Haematologica. 2006 Jul;91(7):873-80. [PubMed:16818273 ]
  3. Nasolodin VV, Zaitseva IP, Gladkikh IP, Voronin SM: [Correction of iron and immune deficiencies in students from a higher humanitarian educational establishment]. Gig Sanit. 2005 Sep-Oct;(5):64-7. [PubMed:16277000 ]
  4. Custodio PJ, Carvalho ML, Nunes F, Pedroso S, Campos A: Direct analysis of human blood (mothers and newborns) by energy dispersive X-ray fluorescence. J Trace Elem Med Biol. 2005;19(2-3):151-8. Epub 2005 Oct 24. [PubMed:16325530 ]
  5. Agarwal MB: Exjade (ICL 670): A new oral iron chelator. J Assoc Physicians India. 2006 Mar;54:214-7. [PubMed:16800349 ]
  6. Cortese S, Konofal E, Lecendreux M, Mouren MC, Bernardina BD: Restless legs syndrome triggered by heart surgery. Pediatr Neurol. 2006 Sep;35(3):223-6. [PubMed:16939866 ]
  7. Barkova EN, Nazarenko EV, Zhdanova EV: Diurnal variations in qualitative composition of breast milk in women with iron deficiency. Bull Exp Biol Med. 2005 Oct;140(4):394-6. [PubMed:16671562 ]
  8. Christoforidis A, Haritandi A, Tsitouridis I, Tsatra I, Tsantali H, Karyda S, Dimitriadis AS, Athanassiou-Metaxa M: Correlative study of iron accumulation in liver, myocardium, and pituitary assessed with MRI in young thalassemic patients. J Pediatr Hematol Oncol. 2006 May;28(5):311-5. [PubMed:16772883 ]
  9. Kom GD, Schwedhelm E, Nielsen P, Boger RH: Increased urinary excretion of 8-iso-prostaglandin F2alpha in patients with HFE-related hemochromatosis: a case-control study. Free Radic Biol Med. 2006 Apr 1;40(7):1194-200. Epub 2005 Dec 13. [PubMed:16545687 ]
  10. Gerlach M, Double KL, Youdim MB, Riederer P: Potential sources of increased iron in the substantia nigra of parkinsonian patients. J Neural Transm Suppl. 2006;(70):133-42. [PubMed:17017520 ]
  11. Jost PJ, Stengel SM, Huber W, Sarbia M, Peschel C, Duyster J: Very severe iron-deficiency anemia in a patient with celiac disease and bulimia nervosa: a case report. Int J Hematol. 2005 Nov;82(4):310-1. [PubMed:16298820 ]
  12. St Pierre TG, Clark PR, Chua-Anusorn W: Measurement and mapping of liver iron concentrations using magnetic resonance imaging. Ann N Y Acad Sci. 2005;1054:379-85. [PubMed:16339686 ]
  13. Clardy SL, Earley CJ, Allen RP, Beard JL, Connor JR: Ferritin subunits in CSF are decreased in restless legs syndrome. J Lab Clin Med. 2006 Feb;147(2):67-73. [PubMed:16459164 ]
  14. Grosse R, Lund U, Caruso V, Fischer R, Janka GE, Magnano C, Engelhardt R, Durken M, Nielsen P: Non-transferrin-bound iron during blood transfusion cycles in beta-thalassemia major. Ann N Y Acad Sci. 2005;1054:429-32. [PubMed:16339692 ]
  15. Anderson LJ, Westwood MA, Prescott E, Walker JM, Pennell DJ, Wonke B: Development of thalassaemic iron overload cardiomyopathy despite low liver iron levels and meticulous compliance to desferrioxamine. Acta Haematol. 2006;115(1-2):106-8. [PubMed:16424659 ]
  16. Matinaho S, Karhumaki P, Parkkinen J: Bicarbonate inhibits the growth of Staphylococcus epidermidis in platelet concentrates by lowering the level of non-transferrin-bound iron. Transfusion. 2005 Nov;45(11):1768-73. [PubMed:16271102 ]
  17. Blanck HM, Cogswell ME, Gillespie C, Reyes M: Iron supplement use and iron status among US adults: results from the third National Health and Nutrition Examination Survey. Am J Clin Nutr. 2005 Nov;82(5):1024-31. [PubMed:16280434 ]
  18. Yarali N, Fisgin T, Duru F, Kara A, Ecin N, Fitoz S, Erden I: Subcutaneous bolus injection of deferoxamine is an alternative method to subcutaneous continuous infusion. J Pediatr Hematol Oncol. 2006 Jan;28(1):11-6. [PubMed:16394886 ]
  19. Walter PB, Fung EB, Killilea DW, Jiang Q, Hudes M, Madden J, Porter J, Evans P, Vichinsky E, Harmatz P: Oxidative stress and inflammation in iron-overloaded patients with beta-thalassaemia or sickle cell disease. Br J Haematol. 2006 Oct;135(2):254-63. [PubMed:17010049 ]
  20. Kontoghiorghes GJ, Kolnagou A: Molecular factors and mechanisms affecting iron and other metal excretion or absorption in health and disease: the role of natural and synthetic chelators. Curr Med Chem. 2005;12(23):2695-709. [PubMed:16305466 ]

Only showing the first 10 proteins. There are 191 proteins in total.


General function:
Involved in binding
Specific function:
N-APP binds TNFRSF21 triggering caspase activation and degeneration of both neuronal cell bodies (via caspase-3) and axons (via caspase-6)
Gene Name:
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Molecular weight:
General function:
Involved in ATP binding
Specific function:
Could be involved in the transport of heme from the mitochondria to the cytosol. Plays a central role in the maturation of cytosolic iron-sulfur (Fe/S) cluster-containing proteins
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in metabolic process
Specific function:
Iron sensor. Binds a 4Fe-4S cluster and functions as aconitase when cellular iron levels are high. Functions as mRNA binding protein that regulates uptake, sequestration and utilization of iron when cellular iron levels are low. Binds to iron-responsive elements (IRES) in target mRNA species when iron levels are low. Binding of a 4Fe-4S cluster precludes RNA binding. Catalyzes the isomerization of citrate to isocitrate via cis-aconitate (By similarity).
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Uniprot ID:
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General function:
Involved in oxidoreductase activity
Specific function:
Terminal component of the liver microsomal stearyl-CoA desaturase system, that utilizes O(2) and electrons from reduced cytochrome b5 to catalyze the insertion of a double bond into a spectrum of fatty acyl-CoA substrates including palmitoyl-CoA and stearoyl-CoA.
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General function:
Involved in cysteamine dioxygenase activity
Specific function:
Not Available
Gene Name:
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Molecular weight:
General function:
Involved in oxidoreductase activity
Specific function:
Dioxygenase that repairs alkylated DNA and RNA containing 1-methyladenine and 3-methylcytosine by oxidative demethylation. Can also repair alkylated DNA containing 1-ethenoadenine (in vitro). Has strong preference for double-stranded DNA. Has low efficiency with single-stranded substrates. Requires molecular oxygen, alpha-ketoglutarate and iron.
Gene Name:
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Molecular weight:
General function:
Involved in oxidoreductase activity
Specific function:
Dioxygenase that repairs alkylated DNA containing 1- methyladenine and 3-methylcytosine by oxidative demethylation. Has a strong preference for single-stranded DNA. May also act on RNA. Requires molecular oxygen, alpha-ketoglutarate and iron
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Molecular weight:
General function:
Involved in peptide-aspartate beta-dioxygenase activity
Specific function:
Isoform 1: specifically hydroxylates an Asp or Asn residue in certain epidermal growth factor-like (EGF) domains of a number of proteins. Isoform 8: membrane-bound Ca(2+)-sensing protein, which is a structural component of the ER-plasma membrane junctions. Isoform 8 regulates the activity of Ca(+2) released-activated Ca(+2) (CRAC) channels in T-cells.
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General function:
Secondary metabolites biosynthesis, transport and catabolism
Specific function:
Symmetrically cleaves beta-carotene into two molecules of retinal. The reaction proceeds in three stages, epoxidation of the 15,15'-double bond, hydration of the double bond leading to ring opening, and oxidative cleavage of the diol formed.
Gene Name:
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General function:
Secondary metabolites biosynthesis, transport and catabolism
Specific function:
Asymmetrically cleaves beta-carotene at the 9',10' double bond resulting in the formation of beta-apo-10'-carotenal and beta-ionone. Besides beta-carotene, lycopene is also oxidatively cleaved. The apocarotenals formed by this enzyme may be the precursors for the biosynthesis of retinoic acid or exert unknown physiological effects.
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General function:
Involved in calcium ion binding
Specific function:
Cotransporter which plays a role in lipoprotein, vitamin and iron metabolism, by facilitating their uptake. Binds to ALB, MB, Kappa and lambda-light chains, TF, hemoglobin, GC, SCGB1A1, APOA1, high density lipoprotein, and the GIF-cobalamin complex. The binding of all ligands required calcium. Serves as important transporter in several absorptive epithelia, including intestine, renal proximal tubules and embryonic yolk sac. Interaction with LRP2 mediates its trafficking throughout vesicles and facilitates the uptake of specific ligands like GC, hemoglobin, ALB, TF and SCGB1A1. Interaction with AMN controls its trafficking to the plasma membrane and facilitates endocytosis of ligands. May play an important role in the development of the peri-implantation embryo through internalization of APOA1 and cholesterol. Binds to LGALS3 at the maternal-fetal interface
Gene Name:
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Molecular weight:
General function:
Involved in transmembrane transport
Specific function:
Has been shown to act both as an intestinal proton- coupled high-affinity folate transporter and as an intestinal heme transporter which mediates heme uptake from the gut lumen into duodenal epithelial cells. The iron is then released from heme and may be transported into the bloodstream. Dietary heme iron is an important nutritional source of iron. Shows a higher affinity for folate than heme
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Only showing the first 10 proteins. There are 191 proteins in total.