Analyze Diet

Ferritin-catalyzed consumption of hydrogen peroxide by amine buffers causes the variable Fe2+ to O2 stoichiometry of iron deposition in horse spleen ferritin.

Abstract: Ferritin catalyzes the oxidation of Fe2+ by O2 to form a reconstituted Fe3+ oxy-hydroxide mineral core, but extensive studies have shown that the Fe2+ to O2 stoichiometry changes with experimental conditions. At Fe2+ to horse spleen ferritin (HoSF) ratios greater than 200, an upper limit of Fe2+ to O2 of 4 is typically measured, indicating O2 is reduced to 2H2O. In contrast, a lower limit of Fe2+ to O2 of approximately 2 is measured at low Fe2+ to HoSF ratios, implicating H2O2 as a product of Fe2+ deposition. Stoichiometric amounts of H2O2 have not been measured, and H2O2 is proposed to react with an unknown system component. Evidence is presented that identifies this component as amine buffers, including 3-N-morpholinopropanesulfonic acid (MOPS), which is widely used in ferritin studies. In the presence of non-amine buffers, the Fe2+ to O2 stoichiometry was approximately 4.0, but at high concentrations of amine buffers (0.10 M) the Fe2+ to O2 stoichiometry is approximately 2.5 for iron loadings of eight to 30 Fe2+ per HoSF. Decreasing the concentration of amine buffer to zero resulted in an Fe2+ to O2 stoichiometry of approximately 4. Direct evidence for amine buffer modification during Fe2+ deposition was obtained by comparing authentic and modified buffers using mass spectrometry, NMR, and thin layer chromatography. Tris(hydroxymethyl)aminomethane, MOPS, and N-methylmorpholine (a MOPS analog) were all rapidly chemically modified during Fe2+ deposition to form N-oxides. Under identical conditions no modification was detected when amine buffer, H2O2, and O2 were combined with Fe2+ or ferritin separately. Thus, a short-lived ferritin intermediate is required for buffer modification by H2O2. Variation of the Fe2+ to O2 stoichiometry versus the Fe2+ to HoSF ratio and the amine buffer concentration are consistent with buffer modification.
Publication Date: 2006-07-29 PubMed ID: 16896807DOI: 10.1007/s00775-006-0141-6Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research investigated the changes in proportions of iron(II) ions and oxygen during iron deposition in horse spleen ferritin, discovering influences of amine buffers and implicating hydrogen peroxide as a product. H2O2 is proposed to react with amine buffers, and this reaction is proved by identifying buffer modification during Fe2+ deposition.

Chemical Reactions in Ferritin

  • Ferritin is a protein complex that assists in oxidation of iron(II) ions (Fe2+) to form a mineral core of iron(III) oxy-hydroxide by using oxygen.
  • The study identifies that under different conditions, the proportions of Fe2+ to oxygen changes, which could influence its biological functions.
  • When the ratio of Fe2+ to the specific ferritin found in the horse spleen (HoSF) is large, the proportion of Fe2+ to oxygen is 4, which signifies that oxygen reduces to water. However, at lower Fe2+ to HoSF ratios, the proportion drops nearly to 2, indicating hydrogen peroxide (H2O2) as a by-product.

Role of Amine Buffers

  • The study proposes an important role of certain types of chemical buffers, specifically amine buffers, in these reactions.
  • In the absence of amine buffers, the ratio of Fe2+ to oxygen remains at 4. However, in the presence of high concentrations of amine buffers, the ratio changes to approximately 2.5.
  • This suggests that H2O2 reacts with these buffers, causing the change in iron deposition stoichiometry. This hypothesis is confirmed by identifying chemical modifications in the buffers when they partake in reactions during Fe2+ deposition.

Buffer Modification Proven

  • Mass spectrometry, NMR, and thin layer chromatography were used to compare buffers before and after the reaction, providing direct evidence of chemical modifications.
  • The buffers used—Tris(hydroxymethyl)aminomethane, MOPS, and N-methylmorpholine—were all found to be chemically altered during Fe2+ deposition to form N-oxides.
  • This alteration in buffers only happened when H2O2, oxygen and Fe2+ were incorporated with ferritin, indicating a short-lived ferritin intermediate as prerequisite for this alteration.
  • These findings hint that the presence and concentration of amine buffers to some extent control the ratio of iron to oxygen during ferritin-assisted iron deposition.

Cite This Article

APA
Zhang B, Wilson PE, Watt GD. (2006). Ferritin-catalyzed consumption of hydrogen peroxide by amine buffers causes the variable Fe2+ to O2 stoichiometry of iron deposition in horse spleen ferritin. J Biol Inorg Chem, 11(8), 1075-1086. https://doi.org/10.1007/s00775-006-0141-6

Publication

ISSN: 0949-8257
NlmUniqueID: 9616326
Country: Germany
Language: English
Volume: 11
Issue: 8
Pages: 1075-1086

Researcher Affiliations

Zhang, Bo
  • Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA.
Wilson, Phillip E
    Watt, Gerald D

      MeSH Terms

      • Amines
      • Animals
      • Buffers
      • Catalysis
      • Ferritins / chemistry
      • Horses
      • Hydrogen Peroxide / chemistry
      • Iron / chemistry
      • Oxygen / chemistry
      • Spleen / chemistry

      References

      This article includes 41 references
      1. Zhao G, Bou-Abdallah F, Arosio P, Levi S, Janus-Chandler C, Chasteen ND. Multiple pathways for mineral core formation in mammalian apoferritin. The role of hydrogen peroxide.. Biochemistry 2003 Mar 18;42(10):3142-50.
        pubmed: 12627982doi: 10.1021/bi027357vgoogle scholar: lookup
      2. Treffry A, Sowerby JM, Harrison PM. Variable stoichiometry of Fe(II)-oxidation in ferritin.. FEBS Lett 1978 Nov 15;95(2):221-4.
        pubmed: 569078doi: 10.1016/0014-5793(78)80998-3google scholar: lookup
      3. Treffry A, Zhao Z, Quail MA, Guest JR, Harrison PM. How the presence of three iron binding sites affects the iron storage function of the ferritin (EcFtnA) of Escherichia coli.. FEBS Lett 1998 Aug 7;432(3):213-8.
        pubmed: 9720927doi: 10.1016/s0014-5793(98)00867-9google scholar: lookup
      4. Murphy PA, Lin JS, Olcott HS. Peroxide oxidation of Tris to a free radical.. Arch Biochem Biophys 1974 Oct;164(2):776-7.
        pubmed: 4376671doi: 10.1016/0003-9861(74)90095-2google scholar: lookup
      5. Bou-Abdallah F, Papaefthymiou GC, Scheswohl DM, Stanga SD, Arosio P, Chasteen ND. mu-1,2-Peroxobridged di-iron(III) dimer formation in human H-chain ferritin.. Biochem J 2002 May 15;364(Pt 1):57-63.
        pubmed: 11988076doi: 10.1042/bj3640057google scholar: lookup
      6. Watt RK, Frankel RB, Watt GD. Redox reactions of apo mammalian ferritin.. Biochemistry 1992 Oct 13;31(40):9673-9.
        pubmed: 1327125doi: 10.1021/bi00155a021google scholar: lookup
      7. Watt GD, Frankel RB, Jacobs D, Huang H, Papaefthymiou GC. Fe2+ and phosphate interactions in bacterial ferritin from Azotobacter vinelandii.. Biochemistry 1992 Jun 23;31(24):5672-9.
        pubmed: 1610815doi: 10.1021/bi00139a035google scholar: lookup
      8. Moënne-Loccoz P, Krebs C, Herlihy K, Edmondson DE, Theil EC, Huynh BH, Loehr TM. The ferroxidase reaction of ferritin reveals a diferric mu-1,2 bridging peroxide intermediate in common with other O2-activating non-heme diiron proteins.. Biochemistry 1999 Apr 27;38(17):5290-5.
        pubmed: 10220314doi: 10.1021/bi990095lgoogle scholar: lookup
      9. Lindsay S, Brosnahan D, Watt GD. Hydrogen peroxide formation during iron deposition in horse spleen ferritin using O2 as an oxidant.. Biochemistry 2001 Mar 20;40(11):3340-7.
        pubmed: 11258954doi: 10.1021/bi001981vgoogle scholar: lookup
      10. Treffry A, Zhao Z, Quail MA, Guest JR, Harrison PM. Iron(II) oxidation by H chain ferritin: evidence from site-directed mutagenesis that a transient blue species is formed at the dinuclear iron center.. Biochemistry 1995 Nov 21;34(46):15204-13.
        pubmed: 7578135doi: 10.1021/bi00046a028google scholar: lookup
      11. Yang X, Le Brun NE, Thomson AJ, Moore GR, Chasteen ND. The iron oxidation and hydrolysis chemistry of Escherichia coli bacterioferritin.. Biochemistry 2000 Apr 25;39(16):4915-23.
        pubmed: 10769150doi: 10.1021/bi992631fgoogle scholar: lookup
      12. Polanams J, Ray AD, Watt RK. Nanophase iron phosphate, iron arsenate, iron vanadate, and iron molybdate minerals synthesized within the protein cage of ferritin.. Inorg Chem 2005 May 2;44(9):3203-9.
        pubmed: 15847428doi: 10.1021/ic048819rgoogle scholar: lookup
      13. Hwang J, Krebs C, Huynh BH, Edmondson DE, Theil EC, Penner-Hahn JE. A short Fe-Fe distance in peroxodiferric ferritin: control of Fe substrate versus cofactor decay?. Science 2000 Jan 7;287(5450):122-5.
        pubmed: 10615044doi: 10.1126/science.287.5450.122google scholar: lookup
      14. Waldo GS, Theil EC. Formation of iron(III)-tyrosinate is the fastest reaction observed in ferritin.. Biochemistry 1993 Dec 7;32(48):13262-9.
        pubmed: 8241182doi: 10.1021/bi00211a039google scholar: lookup
      15. Bauminger ER, Harrison PM, Hechel D, Hodson NW, Nowik I, Treffry A, Yewdall SJ. Iron (II) oxidation and early intermediates of iron-core formation in recombinant human H-chain ferritin.. Biochem J 1993 Dec 15;296 ( Pt 3)(Pt 3):709-19.
        pubmed: 8280069doi: 10.1042/bj2960709google scholar: lookup
      16. Theil EC. Ferritin: structure, gene regulation, and cellular function in animals, plants, and microorganisms.. Annu Rev Biochem 1987;56:289-315.
      17. Xu B, Chasteen ND. Iron oxidation chemistry in ferritin. Increasing Fe/O2 stoichiometry during core formation.. J Biol Chem 1991 Oct 25;266(30):19965-70.
        pubmed: 1939058
      18. Lindsay S, Brosnahan D, Lowery TJ Jr, Crawford K, Watt GD. Kinetic studies of iron deposition in horse spleen ferritin using O2 as oxidant.. Biochim Biophys Acta 2003 Apr 7;1621(1):57-66.
        pubmed: 12667611doi: 10.1016/s0304-4165(03)00030-8google scholar: lookup
      19. Sun S, Arosio P, Levi S, Chasteen ND. Ferroxidase kinetics of human liver apoferritin, recombinant H-chain apoferritin, and site-directed mutants.. Biochemistry 1993 Sep 14;32(36):9362-9.
        pubmed: 8369307doi: 10.1021/bi00087a015google scholar: lookup
      20. Halliwell B, Gutteridge JM. Oxygen free radicals and iron in relation to biology and medicine: some problems and concepts.. Arch Biochem Biophys 1986 May 1;246(2):501-14.
        pubmed: 3010861doi: 10.1016/0003-9861(86)90305-xgoogle scholar: lookup
      21. Van Eden ME, Aust SD. The consequences of hydroxyl radical formation on the stoichiometry and kinetics of ferrous iron oxidation by human apoferritin.. Free Radic Biol Med 2001 Oct 15;31(8):1007-17.
        pubmed: 11595385doi: 10.1016/s0891-5849(01)00677-3google scholar: lookup
      22. Macara IG, Hoy TG, Harrison PM. The formation of ferritin from apoferritin. Kinetics and mechanism of iron uptake.. Biochem J 1972 Jan;126(1):151-62.
        pubmed: 5075227doi: 10.1042/bj1260151google scholar: lookup
      23. Harrison PM, Arosio P. The ferritins: molecular properties, iron storage function and cellular regulation.. Biochim Biophys Acta 1996 Jul 31;1275(3):161-203.
        pubmed: 8695634doi: 10.1016/0005-2728(96)00022-9google scholar: lookup
      24. Zhao G, Bou-Abdallah F, Yang X, Arosio P, Chasteen ND. Is hydrogen peroxide produced during iron(II) oxidation in mammalian apoferritins?. Biochemistry 2001 Sep 11;40(36):10832-8.
        pubmed: 11535059doi: 10.1021/bi011052jgoogle scholar: lookup
      25. Sun S, Chasteen ND. Ferroxidase kinetics of horse spleen apoferritin.. J Biol Chem 1992 Dec 15;267(35):25160-6.
        pubmed: 1460015
      26. Bou-Abdallah F, Zhao G, Mayne HR, Arosio P, Chasteen ND. Origin of the unusual kinetics of iron deposition in human H-chain ferritin.. J Am Chem Soc 2005 Mar 23;127(11):3885-93.
        pubmed: 15771525doi: 10.1021/ja044355kgoogle scholar: lookup
      27. Chen-Barrett Y, Harrison PM, Treffry A, Quail MA, Arosio P, Santambrogio P, Chasteen ND. Tyrosyl radical formation during the oxidative deposition of iron in human apoferritin.. Biochemistry 1995 Jun 20;34(24):7847-53.
        pubmed: 7794895doi: 10.1021/bi00024a008google scholar: lookup
      28. Pereira AS, Small W, Krebs C, Tavares P, Edmondson DE, Theil EC, Huynh BH. Direct spectroscopic and kinetic evidence for the involvement of a peroxodiferric intermediate during the ferroxidase reaction in fast ferritin mineralization.. Biochemistry 1998 Jul 14;37(28):9871-6.
        pubmed: 9665690doi: 10.1021/bi980847wgoogle scholar: lookup
      29. Yang X, Chiancone E, Stefanini S, Ilari A, Chasteen ND. Iron oxidation and hydrolysis reactions of a novel ferritin from Listeria innocua.. Biochem J 2000 Aug 1;349 Pt 3(Pt 3):783-6.
        pubmed: 10903139doi: 10.1042/bj3490783google scholar: lookup
      30. Cheng YG, Chasteen ND. Role of phosphate in initial iron deposition in apoferritin.. Biochemistry 1991 Mar 19;30(11):2947-53.
        pubmed: 2007131doi: 10.1021/bi00225a031google scholar: lookup
      31. Yang X, Chen-Barrett Y, Arosio P, Chasteen ND. Reaction paths of iron oxidation and hydrolysis in horse spleen and recombinant human ferritins.. Biochemistry 1998 Jul 7;37(27):9743-50.
        pubmed: 9657687doi: 10.1021/bi973128agoogle scholar: lookup
      32. Zhao G, Chasteen ND. Oxidation of Good's buffers by hydrogen peroxide.. Anal Biochem 2006 Feb 15;349(2):262-7.
        pubmed: 16289439doi: 10.1016/j.ab.2005.10.005google scholar: lookup
      33. Hodges GR, Ingold KU. Superoxide, amine buffers and tetranitromethane: a novel free radical chain reaction.. Free Radic Res 2000 Nov;33(5):547-50.
        pubmed: 11200087doi: 10.1080/10715760000301081google scholar: lookup
      34. Lowery TJ Jr, Bunker J, Zhang B, Costen R, Watt GD. Kinetic studies of iron deposition in horse spleen ferritin using H2O2 and O2 as oxidants.. Biophys Chem 2004 Oct 1;111(2):173-81.
        pubmed: 15381314doi: 10.1016/j.bpc.2004.05.008google scholar: lookup
      35. Mayer DE, Rohrer JS, Schoeller DA, Harris DC. Fate of oxygen during ferritin iron incorporation.. Biochemistry 1983 Feb 15;22(4):876-80.
        pubmed: 6838829doi: 10.1021/bi00273a026google scholar: lookup
      36. Treffry A, Harrison PM. The binding of ferric iron by ferritin.. Biochem J 1979 Sep 1;181(3):709-16.
        pubmed: 518550doi: 10.1042/bj1810709google scholar: lookup
      37. Jameson GN, Jin W, Krebs C, Perreira AS, Tavares P, Liu X, Theil EC, Huynh BH. Stoichiometric production of hydrogen peroxide and parallel formation of ferric multimers through decay of the diferric-peroxo complex, the first detectable intermediate in ferritin mineralization.. Biochemistry 2002 Nov 12;41(45):13435-43.
        pubmed: 12416989doi: 10.1021/bi026478sgoogle scholar: lookup
      38. Chasteen ND, Harrison PM. Mineralization in ferritin: an efficient means of iron storage.. J Struct Biol 1999 Jun 30;126(3):182-94.
        pubmed: 10441528doi: 10.1006/jsbi.1999.4118google scholar: lookup
      39. Bunker J, Lowry T, Davis G, Zhang B, Brosnahan D, Lindsay S, Costen R, Choi S, Arosio P, Watt GD. Kinetic studies of iron deposition catalyzed by recombinant human liver heavy and light ferritins and Azotobacter vinelandii bacterioferritin using O2 and H2O2 as oxidants.. Biophys Chem 2005 Apr 22;114(2-3):235-44.
        pubmed: 15829358doi: 10.1016/j.bpc.2004.11.008google scholar: lookup
      40. Yang X, Chasteen ND. Ferroxidase activity of ferritin: effects of pH, buffer and Fe(II) and Fe(III) concentrations on Fe(II) autoxidation and ferroxidation.. Biochem J 1999 Mar 15;338 ( Pt 3)(Pt 3):615-8.
        pubmed: 10051430
      41. Beauvais LG, Lippard SJ. Reactions of the peroxo intermediate of soluble methane monooxygenase hydroxylase with ethers.. J Am Chem Soc 2005 May 25;127(20):7370-8.
        pubmed: 15898785doi: 10.1021/ja050865igoogle scholar: lookup

      Citations

      This article has been cited 1 times.
      1. Gehrer CM, Mitterstiller AM, Grubwieser P, Meyron-Holtz EG, Weiss G, Nairz M. Advances in Ferritin Physiology and Possible Implications in Bacterial Infection.. Int J Mol Sci 2023 Feb 28;24(5).
        doi: 10.3390/ijms24054659pubmed: 36902088google scholar: lookup