Record Information
Version 1.0
Update Date 1/22/2018 12:54:54 PM
Metabolite IDPAMDB000172
Name: Iron
Description:Iron 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. 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. 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. Iron may promote both growth of Pseudomonas aeruginosa.
  • Armco iron
  • Carbonyl iron
  • FE
  • Fe(ii)
  • Fe++
  • Fe+2
  • Fe2+
  • Fe++
  • Fe+2
  • Ferrous ion
  • Ferrous iron
  • Ferrovac e
  • Hematite
  • Infed
  • Limonite
  • LOHA
  • Magnetite
  • Malleable iron
  • Metopirone
  • Metyrapone
  • Pzh2M
  • PZHO
  • Remko
  • Suy-B 2
  • Taconite
  • Venofer
  • Wrought iron
Chemical Formula: Fe
Average Molecular Weight: 55.845
Monoisotopic Molecular Weight: 55.934942133
CAS number: 7439-89-6
IUPAC Name:??-iron(2+) ion
Traditional IUPAC Name: ??-iron(2+) ion
Chemical Taxonomy
Taxonomy DescriptionThis compound belongs to the class of inorganic compounds known as homogeneous transition metal compounds. These are inorganic compounds containing only metal atoms,with the largest atom being a transition metal atom.
Kingdom Inorganic compounds
Super ClassHomogeneous metal compounds
Class Homogeneous transition metal compounds
Sub ClassNot Available
Direct Parent Homogeneous transition metal compounds
Alternative Parents Not Available
  • Homogeneous transition metal
  • Acyclic compound
Molecular Framework Acyclic compounds
External Descriptors
Physical Properties
State: Solid
Melting point: 1538 °C
Experimental Properties:
Predicted Properties
Physiological Charge2ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area0 Å2ChemAxon
Rotatable Bond Count0ChemAxon
Refractivity0 m3·mol-1ChemAxon
Polarizability1.78 Å3ChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Biological Properties
Cellular Locations: Cytoplasm
Adenosine triphosphate + FADH2 + 2 Iron + Water + SufBCD scaffold complex + 2 SufSE with bound sulfur > ADP + FAD +7 Hydrogen ion + Phosphate + SufBCD with bound [2Fe-2S] cluster +2 SufSE sulfur acceptor complex
Adenosine triphosphate + FADH2 + 2 Iron + Water + SufBCD with bound [2Fe-2S] cluster + 2 SufSE with bound sulfur > ADP + FAD +7 Hydrogen ion + Phosphate + SufBCD with two bound [2Fe-2S] clusters +2 SufSE sulfur acceptor complex
FADH2 + 2 Iron + 2 IscS with bound sulfur + IscU scaffold protein > FAD +6 Hydrogen ion +2 IscS sulfur acceptor protein + IscU with bound [2Fe-2S] cluster
FADH2 + 2 Iron + 2 IscS with bound sulfur + IscU with bound [2Fe-2S] cluster > FAD +6 Hydrogen ion +2 IscS sulfur acceptor protein + IscU with two bound [2Fe-2S] clusters
4 Iron + 4 Hydrogen ion + Oxygen >4 Fe3+ +2 Water
[4Fe-4S] iron-sulfur cluster + 2 S-Adenosylmethionine + Hydrogen ion + NAD + octanoate (protein bound) > [2Fe-2S] iron-sulfur cluster +2 5'-Deoxyadenosine +2 Iron + lipoate (protein bound) +2 L-Methionine + NADH
Iron + Sirohydrochlorin >3 Hydrogen ion + Siroheme
Adenosine triphosphate + Water + Iron > ADP + Iron + Hydrogen ion + Phosphate
Adenosine triphosphate + Water + Iron > ADP + Iron + Hydrogen ion + Phosphate
FADH2 + 2 Fe3+ > FAD +2 Iron +2 Hydrogen ion
[3Fe-4S] damaged iron-sulfur cluster + Iron > [4Fe-4S] iron-sulfur cluster
FADH2 + 2 Ferroxamine > FAD +2 Iron +2 ferroxamine minus Fe(3) +2 Hydrogen ion
2 Ferroxamine + FMNH >2 Iron +2 ferroxamine minus Fe(3) + Flavin Mononucleotide +2 Hydrogen ion
2 Ferroxamine + Reduced riboflavin >2 Iron +2 ferroxamine minus Fe(3) +2 Hydrogen ion + Riboflavin
Hydrogen ion + Hydrogen peroxide + Iron > hydroxyl radical + OH<SUP>-</SUP> + Fe<SUP>3+</SUP>
Oxygen + Iron > Superoxide anion + Fe<SUP>3+</SUP>
Iron + Protoporphyrin IX > Heme + Hydrogen ion
Iron + Hydrogen ion + Oxygen > Fe<SUP>3+</SUP> + Water
Iron + a siderophore + NADP < an Fe(III)-siderophore + NADPH + Hydrogen ion
Iron + (2,3-dihydroxybenzoylserine)<sub>3</sub> + NADP < ferric 2,3-dihydroxybenzoylserine + NADPH + Hydrogen ion

Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, NegativeNot Available
  • Agarwal MB: Exjade (ICL 670): A new oral iron chelator. J Assoc Physicians India. 2006 Mar;54:214-7. Pubmed: 16800349
  • 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
  • Appenzeller, B. M., Yanez, C., Jorand, F., Block, J. C. (2005). "Advantage provided by iron for Escherichia coli growth and cultivability in drinking water." Appl Environ Microbiol 71:5621-5623. Pubmed: 16151163
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • Kanehisa, M., Goto, S., Sato, Y., Furumichi, M., Tanabe, M. (2012). "KEGG for integration and interpretation of large-scale molecular data sets." Nucleic Acids Res 40:D109-D114. Pubmed: 22080510
  • Keseler, I. M., Collado-Vides, J., Santos-Zavaleta, A., Peralta-Gil, M., Gama-Castro, S., Muniz-Rascado, L., Bonavides-Martinez, C., Paley, S., Krummenacker, M., Altman, T., Kaipa, P., Spaulding, A., Pacheco, J., Latendresse, M., Fulcher, C., Sarker, M., Shearer, A. G., Mackie, A., Paulsen, I., Gunsalus, R. P., Karp, P. D. (2011). "EcoCyc: a comprehensive database of Escherichia coli biology." Nucleic Acids Res 39:D583-D590. Pubmed: 21097882
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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
Synthesis Reference: Not Available
Material Safety Data Sheet (MSDS) Download (PDF)
External Links:
Pubchem Compound ID23925
Kegg IDC00023
ChemSpider ID25394
BioCyc IDFE+2
EcoCyc IDFE+2
Ligand ExpoFE2


General function:
Involved in metabolic process
Specific function:
Catalyzes the removal of elemental sulfur and selenium atoms from cysteine and selenocysteine to produce alanine. Functions as a sulfur delivery protein for NAD, biotin and Fe-S cluster synthesis. Transfers sulfur on 'Cys-456' of thiI in a transpersulfidation reaction. Transfers sulfur on 'Cys-19' of tusA in a transpersulfidation reaction. Functions also as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate
Gene Name:
Locus Tag:
Molecular weight:
44.7 kDa
L-cysteine + acceptor = L-alanine + S-sulfanyl-acceptor.
General function:
Involved in methyltransferase activity
Specific function:
Multifunctional enzyme that catalyzes the SAM-dependent methylation of uroporphyrinogen III at position C-2 and C-7 to form precorrin-2 and then position C-12 or C-18 to form trimethylpyrrocorphin 2. It also catalyzes the conversion of precorrin-2 into siroheme. This reaction consists of the NAD- dependent oxidation of precorrin-2 into sirohydrochlorin and its subsequent ferrochelation into siroheme
Gene Name:
Locus Tag:
Molecular weight:
50.4 kDa
S-adenosyl-L-methionine + uroporphyrinogen III = S-adenosyl-L-homocysteine + precorrin-1.
S-adenosyl-L-methionine + precorrin-1 = S-adenosyl-L-homocysteine + precorrin-2.
Precorrin-2 + NAD(+) = sirohydrochlorin + NADH.
Siroheme + 2 H(+) = sirohydrochlorin + Fe(2+).
General function:
Involved in ferrochelatase activity
Specific function:
Catalyzes the ferrous insertion into protoporphyrin IX
Gene Name:
Locus Tag:
Molecular weight:
38.6 kDa
Protoheme + 2 H(+) = protoporphyrin + Fe(2+).
General function:
Involved in catalytic activity
Specific function:
Catalyzes the radical-mediated insertion of two sulfur atoms into the C-6 and C-8 positions of the octanoyl moiety bound to the lipoyl domains of lipoate-dependent enzymes, thereby converting the octanoylated domains into lipoylated derivatives. Free octanoate is not a substrate for lipA
Gene Name:
Locus Tag:
Molecular weight:
32.7 kDa
Protein N(6)-(octanoyl)lysine + 2 sulfur + 2 S-adenosyl-L-methionine = protein N(6)-(lipoyl)lysine + 2 L-methionine + 2 5'-deoxyadenosine.
General function:
Involved in GTP binding
Specific function:
GTP-driven Fe(2+) uptake system
Gene Name:
Locus Tag:
Molecular weight:
82.5 kDa
General function:
Involved in iron ion binding
Specific function:
May be involved in the formation or repair of [Fe-S] clusters present in iron-sulfur proteins (Potential)
Gene Name:
Locus Tag:
Molecular weight:
13.8 kDa
General function:
Not Available
Specific function:
Not Available
Gene Name:
Locus Tag:
Molecular weight:
17.9 kDa
General function:
Inorganic ion transport and metabolism
Specific function:
May perform analogous functions in iron detoxification and storage to that of animal ferritins
Gene Name:
Locus Tag:
Molecular weight:
18.6 kDa
4 Fe(2+) + 4 H(+) + O(2) = 4 Fe(3+) + 2 H(2)O.


General function:
Involved in GTP binding
Specific function:
GTP-driven Fe(2+) uptake system
Gene Name:
Locus Tag:
Molecular weight:
82.5 kDa