Marten Wikstrom

Summary

Affiliation: University of Helsinki
Country: Finland

Publications

  1. ncbi Towards the mechanism of proton pumping by the haem-copper oxidases
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1757:1047-51. 2006
  2. doi How I became a biochemist
    Marten Wikstrom
    Institute of Biotechnology, University of Helsinki, Helsinki, Finland
    IUBMB Life 60:414-7. 2008
  3. pmc Gating of proton and water transfer in the respiratory enzyme cytochrome c oxidase
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, Program for Structural Biology and Biophysics, University of Helsinki, PB 65 Viikinkaari 1, 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 102:10478-81. 2005
  4. ncbi Cytochrome c oxidase: 25 years of the elusive proton pump
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, Biocenter 3 Viikinkaari 1 PB 65, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1655:241-7. 2004
  5. ncbi Water-gated mechanism of proton translocation by cytochrome c oxidase
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology and Biocentrum Helsinki, University of Helsinki, PB 65 Viikinkaari 1, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1604:61-5. 2003
  6. ncbi Proton translocation by cytochrome c oxidase in different phases of the catalytic cycle
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, Programme for Structural Biology and Biophysics, University of Helsinki, PB 65, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1555:128-32. 2002
  7. ncbi Ultrafast haem-haem electron transfer in cytochrome c oxidase
    M I Verkhovsky
    Helsinki Bioenergetics Group, Institute of Biotechnology and Biocentrum Helsinki, Biocenter 2, Room 2011, P O Box 56, University of Helsinki, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1506:143-6. 2001
  8. ncbi The role of the D- and K-pathways of proton transfer in the function of the haem-copper oxidases
    M Wikstrom
    Department of Medical Chemistry, Institute of Biomedical Sciences and Biocentrum Helsinki, University of Helsinki, Finland
    Biochim Biophys Acta 1459:514-20. 2000
  9. ncbi Proton translocation by bacteriorhodopsin and heme-copper oxidases
    M Wikstrom
    Helsinki Bioenergetics Group, University of Helsinki, Finland
    Curr Opin Struct Biol 8:480-8. 1998
  10. ncbi The D-channel of cytochrome oxidase: an alternative view
    Marten Wikstrom
    University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1807:1273-8. 2011

Collaborators

Detail Information

Publications74

  1. ncbi Towards the mechanism of proton pumping by the haem-copper oxidases
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1757:1047-51. 2006
    ..The different kinetics of electron-coupled proton transfer in different steps of the catalytic cycle may be related to differences in the driving force due to different Em values of the electron acceptor in the binuclear site...
  2. doi How I became a biochemist
    Marten Wikstrom
    Institute of Biotechnology, University of Helsinki, Helsinki, Finland
    IUBMB Life 60:414-7. 2008
  3. pmc Gating of proton and water transfer in the respiratory enzyme cytochrome c oxidase
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, Program for Structural Biology and Biophysics, University of Helsinki, PB 65 Viikinkaari 1, 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 102:10478-81. 2005
    ..Exit of product water is observed through the same arginine/propionate gate, which provides an explanation for the observed extraordinary spatial specificity of water expulsion from the enzyme...
  4. ncbi Cytochrome c oxidase: 25 years of the elusive proton pump
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, Biocenter 3 Viikinkaari 1 PB 65, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1655:241-7. 2004
    ..In the hope of accelerating progress, some of these will be reviewed here, together with a brief presentation of a novel proton pump mechanism, and of the emergence of a molecular basis for control of its efficiency...
  5. ncbi Water-gated mechanism of proton translocation by cytochrome c oxidase
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology and Biocentrum Helsinki, University of Helsinki, PB 65 Viikinkaari 1, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1604:61-5. 2003
    ..This pumping mechanism explains the unique arrangement of the metal cofactors in the structure. It is consistent with the large body of biochemical data, and is shown to be plausible by molecular dynamics simulations...
  6. ncbi Proton translocation by cytochrome c oxidase in different phases of the catalytic cycle
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, Programme for Structural Biology and Biophysics, University of Helsinki, PB 65, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1555:128-32. 2002
    ..This phenomenon might be related to the previously described "pulsed" vs. "resting" and "fast" vs."slow" forms of haem-copper oxidases...
  7. ncbi Ultrafast haem-haem electron transfer in cytochrome c oxidase
    M I Verkhovsky
    Helsinki Bioenergetics Group, Institute of Biotechnology and Biocentrum Helsinki, Biocenter 2, Room 2011, P O Box 56, University of Helsinki, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1506:143-6. 2001
    ..We ascribe this to the true haem-haem electron tunnelling rate between the haem groups...
  8. ncbi The role of the D- and K-pathways of proton transfer in the function of the haem-copper oxidases
    M Wikstrom
    Department of Medical Chemistry, Institute of Biomedical Sciences and Biocentrum Helsinki, University of Helsinki, Finland
    Biochim Biophys Acta 1459:514-20. 2000
    ..The unique K-pathway proton may be specifically required to aid O-O bond scission by the haem-copper oxidases...
  9. ncbi Proton translocation by bacteriorhodopsin and heme-copper oxidases
    M Wikstrom
    Helsinki Bioenergetics Group, University of Helsinki, Finland
    Curr Opin Struct Biol 8:480-8. 1998
    ..A comparison reveals common structural and functional features that may be unique to the primary proton pumps in biology...
  10. ncbi The D-channel of cytochrome oxidase: an alternative view
    Marten Wikstrom
    University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1807:1273-8. 2011
    ..This article is part of a Special Issue entitled: Allosteric cooperativity in respiratory proteins...
  11. ncbi Mechanism and energetics of proton translocation by the respiratory heme-copper oxidases
    Marten Wikstrom
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Programme, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, FI 00014 University of Helsinki, Finland
    Biochim Biophys Acta 1767:1200-14. 2007
    ..Special emphasis is made on side-reactions that may short-circuit the pump, and the means by which these may be avoided. We will also discuss the most prominent proton pumping mechanisms proposed to date in relation to these data...
  12. doi The role of the invariant glutamate 95 in the catalytic site of Complex I from Escherichia coli
    Liliya Euro
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, Finland
    Biochim Biophys Acta 1787:68-73. 2009
    ....
  13. ncbi Conserved lysine residues of the membrane subunit NuoM are involved in energy conversion by the proton-pumping NADH:ubiquinone oxidoreductase (Complex I)
    Liliya Euro
    Helsinki Bioenergetics Group, Institute of Biotechnology, PO Box 65 Viikinkaari 1 FIN 00014 University of Helsinki, Finland
    Biochim Biophys Acta 1777:1166-72. 2008
    ..A tentative principle of proton translocation by Complex I is suggested based on electrostatic interactions of lysines in the membrane subunits...
  14. doi Electrostatic interactions between FeS clusters in NADH:ubiquinone oxidoreductase (Complex I) from Escherichia coli
    Liliya Euro
    Helsinki Bioenergetics Group, Institute of Biotechnology, P O Box 65, Viikinkaari 1 00014 University of Helsinki, Helsinki, Finland
    Biochemistry 47:3185-93. 2008
    ..The observed redox titration curves are discussed in terms of intrinsic electrostatic interactions between FeS centers in complex I. A model showing shifts of E m due to the electrostatic interaction between the centers is presented...
  15. pmc Real-time electron transfer in respiratory complex I
    Marina L Verkhovskaya
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Program, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 105:3763-7. 2008
    ..Possible consequences of these findings for the proton translocation mechanism are discussed...
  16. ncbi Activation of isolated NADH:ubiquinone reductase I (complex I) from Escherichia coli by detergent and phospholipids. Recovery of ubiquinone reductase activity and changes in EPR signals of iron-sulfur clusters
    Liliya Sinegina
    Helsinki Bioenergetics Group, Institute of Biotechnology, PO Box 65 Viikinkaari 1 FIN 00014 University of Helsinki, Finland
    Biochemistry 44:8500-6. 2005
    ..895, 1.904, 2.05, which corresponds to the parameters reported for the N2 cluster. This data indicates conformational rearrangements of catalytic importance in complex I upon binding of phospholipids...
  17. doi High affinity cation-binding sites in Complex I from Escherichia coli
    Liliya Euro
    Helsinki Bioenergetics Group, Institute of Biotechnology, PO Box 65 Viikinkaari 1 00014 University of Helsinki, Finland
    Biochim Biophys Acta 1787:1024-8. 2009
    ..K(+) and La(3+) do not occupy the same site. Possible localization of these metal-binding sites and their implication in catalysis are discussed...
  18. pmc The protonation state of the cross-linked tyrosine during the catalytic cycle of cytochrome c oxidase
    Elena A Gorbikova
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, P O Box 65, Viikinkaari 1, FI 00014 Helsinki, Finland
    J Biol Chem 283:34907-12. 2008
    ..We found that complete reprotonation of the tyrosine is linked to the formation of the one-electron reduced state coupled to reduction of the Cu(B) site...
  19. ncbi Proton-coupled electron transfer drives the proton pump of cytochrome c oxidase
    Ilya Belevich
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FIN 00014 University of Helsinki, Helsinki, Finland
    Nature 440:829-32. 2006
    ..This reaction drives the proton pump and occurs before relaxation steps in which protons are taken up from the aqueous space on one side of the membrane and released on the other...
  20. pmc Initiation of the proton pump of cytochrome c oxidase
    Ilya Belevich
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, FI 00014, Helsinki, Finland
    Proc Natl Acad Sci U S A 107:18469-74. 2010
    ..A conserved tyrosine in the so-called D-channel is identified as a potential proton donor that determines the efficiency of this reaction...
  21. ncbi Dynamics of the glutamic acid 242 side chain in cytochrome c oxidase
    Anne Tuukkanen
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Programme, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1767:1102-6. 2007
    ....
  22. ncbi Elementary steps of proton translocation in the catalytic cycle of cytochrome oxidase
    Michael I Verkhovsky
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FIN 00014 University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1757:401-7. 2006
    ..We discuss this difference in terms of different driving forces and relate our results, and data from the literature, to proposed mechanisms of proton pumping in cytochrome c oxidase...
  23. ncbi Role of the conserved arginine 274 and histidine 224 and 228 residues in the NuoCD subunit of complex I from Escherichia coli
    Galina Belevich
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, P O Box 65 Viikinkaari 1, Helsinki FIN 00014, Finland
    Biochemistry 46:526-33. 2007
    ....
  24. doi Mechanism and energetics by which glutamic acid 242 prevents leaks in cytochrome c oxidase
    Ville R I Kaila
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Program, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1787:1205-14. 2009
    ..Our model provides a suggestion for why reduction of the former state is coupled to proton translocation while reduction of the latter is not...
  25. pmc Active site of cytochrome cbb3
    Virve Rauhamäki
    Helsinki Bioenergetics Group, Program for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P O Box 65 Viikinkaari 1, 00014 Helsinki, Finland
    J Biol Chem 284:11301-8. 2009
    ..These results strongly suggest that Glu-383 is involved in hydrogen bonding to the proximal His-405 ligand of heme b(3), a unique interaction among heme-copper oxidases...
  26. doi Dynamic water networks in cytochrome cbb3 oxidase
    Vivek Sharma
    Helsinki Bioenergetics Group, Programme for Structural Biology and Biophysics, Institute of Biotechnology, PB 65 Viikinkaari 1, University of Helsinki, 00014, Finland
    Biochim Biophys Acta 1817:726-34. 2012
    ..Protonation of Glu323 provides a mechanism to tune the redox potential of heme b(3) with possible implications for proton pumping...
  27. pmc Probing the mechanistic role of the long α-helix in subunit L of respiratory Complex I from Escherichia coli by site-directed mutagenesis
    Galina Belevich
    Helsinki Bioenergetics Group, Institute of Biotechnology, FIN 00014, University of Helsinki, Helsinki, Finland
    Mol Microbiol 82:1086-95. 2011
    ..The implications of these results for the proton pumping mechanism of Complex I are discussed...
  28. pmc Glutamic acid 242 is a valve in the proton pump of cytochrome c oxidase
    Ville R I Kaila
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 1, P O Box 65, 00014, Helsinki, Finland
    Proc Natl Acad Sci U S A 105:6255-9. 2008
    ..Suppression of proton leakage is particularly important in mitochondria under physiological conditions, where production of ATP takes place in the presence of a high electrochemical proton gradient...
  29. ncbi Prevention of leak in the proton pump of cytochrome c oxidase
    Ville R I Kaila
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Programme, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, 00014 University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1777:890-2. 2008
    ....
  30. ncbi Electron and proton transfer in the arginine-54-methionine mutant of cytochrome c oxidase from Paracoccus denitrificans
    A Jasaitis
    Helsinki Bioenergetics Group, Department of Medical Chemistry, Institute of Biomedical Sciences and Biocentrum Helsinki, University of Helsinki, Finland
    Biochemistry 40:5269-74. 2001
    ..From this we conclude that the completely (4e(-)) reduced enzyme is fully capable of proton translocation...
  31. ncbi Proton-coupled electron equilibrium in soluble and membrane-bound cytochrome c oxidase from Paracoccus denitrificans
    Ilya Belevich
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FIN 00014 Helsinki, Finland
    Biochemistry 45:4000-6. 2006
    ..The possible mechanism of such dramatic change in the rate of proton transfer is discussed...
  32. ncbi Redox titration of all electron carriers of cytochrome c oxidase by Fourier transform infrared spectroscopy
    Elena A Gorbikova
    Program for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, FIN 00014 Helsinki, Finland
    Biochemistry 45:5641-9. 2006
    ..For example, the well-known band shift at 1737/1746 cm(-)(1) corresponding to the protonated glutamic acid E278 correlated with oxidoreduction of heme a...
  33. pmc Mechanistic stoichiometry of proton translocation by cytochrome cbb3
    Virve Rauhamäki
    Helsinki Bioenergetics Group, Program for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, 00014, Helsinki, Finland
    Proc Natl Acad Sci U S A 109:7286-91. 2012
    ..The mechanism of proton pumping thus differs from that of the aa(3)-type oxidases of mitochondria and bacteria...
  34. doi A combined quantum chemical and crystallographic study on the oxidized binuclear center of cytochrome c oxidase
    Ville R I Kaila
    Institute of Biotechnology, University of Helsinki, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1807:769-78. 2011
    ..We show that the presence of O(2) is consistent with the X-ray data. We also discuss how other structures, such as a mixture of the aqueous species (H(2)O+OH(-) and H(2)O) and chloride fit the experimental data...
  35. pmc The proton donor for O-O bond scission by cytochrome c oxidase
    Elena A Gorbikova
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, P O Box 65 Viikinkaari 1, FI 00014, Helsinki, Finland
    Proc Natl Acad Sci U S A 105:10733-7. 2008
    ....
  36. pmc Stoichiometry of proton translocation by respiratory complex I and its mechanistic implications
    Marten Wikstrom
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FI 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 109:4431-6. 2012
    ..In a rough mechanistic model, we suggest a concerted proton translocation mechanism in the three homologous and tightly packed antiporter-like subunits L, M, and N of the proton-translocating membrane domain of complex I...
  37. pmc Exploring the proton pump mechanism of cytochrome c oxidase in real time
    Ilya Belevich
    Helsinki Bioenergetics Group, Program for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P O Box 65, FI 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 104:2685-90. 2007
    ..8 ms, another proton is transferred from the inside to the heme a(3)/Cu(B) center, and the electron is transferred to Cu(B). Finally, in 2.6 ms, the preloaded proton is released from the pump site to the opposite side of the membrane...
  38. doi The identity of the transient proton loading site of the proton-pumping mechanism of cytochrome c oxidase
    Ville R I Kaila
    Helsinki Bioenergetics Group, Programme of Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P O Box 65, FI 00014 Helsinki, Finland
    Biochim Biophys Acta 1807:80-4. 2011
    ..These findings suggest that the propionate region of heme a₃ fulfills the criteria of the pump site in the proton translocation mechanism of CcO...
  39. ncbi Time-resolved ATR-FTIR spectroscopy of the oxygen reaction in the D124N mutant of cytochrome c oxidase from Paracoccus denitrificans
    Elena A Gorbikova
    Structural Biology and Biophysics Program, Institute of Biotechnology, PB 65 Viikinkaari 1, FIN 00014 University of Helsinki, Helsinki, Finland
    Biochemistry 46:13141-8. 2007
    ..The blockage of the D-pathway in this mutant for the first time allowed direct detection of deprotonation of Glu 278 and its reprotonation during oxidation of cytochrome oxidase by O2...
  40. pmc Computational study of the activated O(H) state in the catalytic mechanism of cytochrome c oxidase
    Vivek Sharma
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FI 00014, Helsinki, Finland
    Proc Natl Acad Sci U S A 110:16844-9. 2013
    ..Our calculations also suggest that the neutral radical form of the cross-linked tyrosine in the binuclear site may be more significant in the catalytic cycle than suspected so far...
  41. doi Role of Ca(2+) in structure and function of Complex I from Escherichia coli
    Marina Verkhovskaya
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, Finland
    Biochim Biophys Acta 1807:36-41. 2011
    ..coli Complex I, analogous to Nqo15 in the T. thermophilus enzyme, or another component of the native membrane that affects the affinity and/or accessibility of the Ca(2+) binding site...
  42. pmc Interheme electron tunneling in cytochrome c oxidase
    Ville R I Kaila
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Programme, Institute of Biotechnology, University of Helsinki, PO Box 65, FI 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 107:21470-5. 2010
    ..We argue that this modification may be necessary at short donor/acceptor distances comparable to the donor/acceptor radii...
  43. ncbi Protolytic reactions on reduction of cytochrome c oxidase studied by ATR-FTIR spectroscopy
    Elena A Gorbikova
    Program for Structural Biology and Biophysics, Institute of Biotechnology, PB 65 Viikinkaari 1, University of Helsinki, Helsinki FIN 00014, Finland
    Biochemistry 46:4177-83. 2007
    ..This feature of an asymmetric water molecule may belong to water that is produced in the binuclear center upon reduction or to a structured water molecule that loses a hydrogen bond...
  44. doi Stabilization of the peroxy intermediate in the oxygen splitting reaction of cytochrome cbb(3)
    Vivek Sharma
    University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1807:813-8. 2011
    ..The major molecular basis for this stabilization is a glutamate residue, polarizing the proximal histidine ligand of heme b(3) in the active site...
  45. ncbi An elementary reaction step of the proton pump is revealed by mutation of tryptophan-164 to phenylalanine in cytochrome c oxidase from Paracoccus denitrificans
    Camilla Ribacka
    Helsinki Bioenergetics Group, Program for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, FIN 00014, Helsinki, Finland
    Biochemistry 44:16502-12. 2005
    ....
  46. ncbi Role of the PR intermediate in the reaction of cytochrome c oxidase with O2
    J E Morgan
    Helsinki Bioenergetics Group, Institute of Biotechnology, Biocenter 2 (Viikinaari 5, Room 2011, PB 56, University of Helsinki, FI-00014 Helsinki, Finland
    Biochemistry 40:6882-92. 2001
    ..The spectroscopic differences between these three intermediates are evaluated. The P(R) state has a key role as an initiator of proton translocation by the enzyme, and the thermodynamic and electrostatic bases for this are discussed...
  47. ncbi K+-dependent Na+ transport driven by respiration in Escherichia coli cells and membrane vesicles
    M L Verkhovskaya
    Helsinki Bioenergetics Group, Institute of Biomedical Sciences, Department of Medical Chemistry, University of Helsinki, Finland
    Biochim Biophys Acta 1273:207-16. 1996
    ..Such an effect may be expected if the Na+, K+/H+ antiporter normally operates in tight conjunction with respiratory chain complexes, thus exhibiting some phenomenological properties of a primary redox-linked sodium pump...
  48. ncbi Sequence analysis of the cbb3 oxidases and an atomic model for the Rhodobacter sphaeroides enzyme
    Vivek Sharma
    Helsinki Bioenergetics Group, Programme for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, FIN 00014 Helsinki, Finland
    Biochemistry 45:5754-65. 2006
    ..An analogue of the D-channel is not found, but an alternative channel might form around helix 9. A preliminary packing model of the trimeric enzyme is also presented...
  49. pmc The catalytic cycle of cytochrome c oxidase is not the sum of its two halves
    Dmitry Bloch
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, PB 65 Viikinkaari 1, FIN 00014, Helsinki, Finland
    Proc Natl Acad Sci U S A 101:529-33. 2004
    ..The efficiency of ATP synthesis might be regulated by switching between the two catalytic pathways...
  50. doi Active site intermediates in the reduction of O(2) by cytochrome oxidase, and their derivatives
    Marten Wikstrom
    University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1817:468-75. 2012
    ..The P and F states formed artificially by reacting cytochrome oxidase with hydrogen peroxide are especially scrutinised, and some novel interpretations will be given that may account for previously unexplained observations...
  51. doi Redox-coupled proton transfer in the active site of cytochrome cbb3
    Vivek Sharma
    Helsinki Bioenergetics Group, Structural Biology and Biophysics Programme, Institute of Biotechnology, PB 65 Viikinkaari 1, University of Helsinki, FIN 00014, Helsinki, Finland
    Biochim Biophys Acta 1797:1512-20. 2010
    ....
  52. doi Modeling the active-site structure of the cbb3-type oxidase from Rhodobacter sphaeroides
    Vivek Sharma
    Helsinki Bioenergetics Group, Programme for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland
    Biochemistry 47:4221-7. 2008
    ..The relationship between sequence and functional data for defining the subfamily is discussed...
  53. ncbi Control of electron delivery to the oxygen reduction site of cytochrome c oxidase: a role for protons
    M I Verkhovsky
    Department of Medical Chemistry, University of Helsinki, Finland
    Biochemistry 34:7483-91. 1995
    ..Important consequences of this mechanism for the function of the enzyme and for the respiratory chain as a whole are discussed...
  54. doi Oxidoreduction properties of bound ubiquinone in Complex I from Escherichia coli
    Marina Verkhovskaya
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, PO Box 65 Viikinkaari 1, FIN 00014 Helsinki, Finland Electronic address
    Biochim Biophys Acta 1837:246-50. 2014
    ..This thermodynamic property of bound ubiquinone has important implications for the mechanism by which Complex I catalyzes proton translocation. ..
  55. ncbi Change in electron and spin density upon electron transfer to haem
    Mikael P Johansson
    Department of Chemistry, P O Box 55 A I Virtanens Plats 1, University of Helsinki, FIN 00014, Helsinki, Finland
    Biochim Biophys Acta 1553:183-7. 2002
    ..The lost individuality of the electron added to the haem on reduction is another example of the importance of quantum mechanical effects in biological systems...
  56. ncbi Steady-state redox behavior of cytochrome c, cytochrome a, and CuA of cytochrome c oxidase in intact rat liver mitochondria
    J E Morgan
    Department of Medical Chemistry, University of Helsinki, Finland
    Biochemistry 30:948-58. 1991
    ..Interestingly, in these circumstances (azide and uncoupler present), Fea behaves as if it were no longer the kinetically controlling electron donor to the bimetallic center...
  57. ncbi pH dependence of proton translocation by Escherichia coli
    M Verkhovskaya
    Department of Medical Chemistry, University of Helsinki, Finland
    J Biol Chem 267:14559-62. 1992
    ..This makes it improbable that the Na+/H+ antiporter is responsible. The most likely explanation for our finding is that there is a "slip" in the proton-pumping mechanism of cytochrome o at high pH...
  58. ncbi Identification of a "peroxy" intermediate in cytochrome bo3 of Escherichia coli
    J E Morgan
    Helsinki Bioenergetics Group, Department of Medical Chemistry, University of Helsinki, Finland
    Biochemistry 34:15633-7. 1995
    ..This intermediate subsequently relaxes into the "ferryl" species which has been described previously. We conclude that the oxygen reaction is similar in the cytochrome c and quinol oxidases...
  59. ncbi The K-pathway revisited: a computational study on cytochrome c oxidase
    Anne Tuukkanen
    Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FIN 00014 University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1757:1117-21. 2006
    ..Lys(I)-319 is also found to interact electrostatically with the conserved residue Glu(II)-62 in subunit II. These results are discussed in relation to the role of the K-pathway in oxidase function...
  60. pmc Identification of a histidine-tyrosine cross-link in the active site of the cbb3-type cytochrome c oxidase from Rhodobacter sphaeroides
    Virve Rauhamäki
    Helsinki Bioenergetics Group, Program for Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P O Box 65, Viikinkaari 1, 00014 Helsinki, Finland
    Proc Natl Acad Sci U S A 103:16135-40. 2006
    ..These results suggest a universal functional importance of the histidine-tyrosine cross-link in the mechanism of O(2) reduction by all heme-copper oxidases...
  61. ncbi The terminal quinol oxidases of Bacillus subtilis have different energy conservation properties
    M Lauraeus
    Department of Medical Chemistry, University of Helsinki, Finland
    J Biol Chem 268:11470-3. 1993
    ..This protein did not exhibit oxidase activity and did not have the characteristics of members of the conserved terminal oxidase family...
  62. ncbi The "ferrous-oxy" intermediate in the reaction of dioxygen with fully reduced cytochromes aa3 and bo3
    M I Verkhovsky
    Department of Medical Chemistry, University of Helsinki, Finland
    Biochemistry 35:16241-6. 1996
    ..In cytochrome bo3, the ferrous-oxy intermediate, resolved by optical absorbance spectroscopy for the first time, appears with a time constant of 11 microseconds and has a broad maximum near 570 nm...
  63. ncbi The respiration-driven active sodium transport system in E. coli does not function with lithium
    M L Verkhovskaya
    Helisinki Bioenegetics Group, Department of Medical Chemistry, Institute of Biomedical Sciences, University of Helsinki, Finland
    FEBS Lett 388:217-8. 1996
    ..coli [Verkhovskaya, M.L., Verkhovsky, M.I. and Wikstrom, M. (1996) Biochim. Biophys. Acta 1273, 207-216]. In contrast to the Na+/H+ antiporters, the AST system is inhibited by Li+...
  64. ncbi Deletion of one of two Escherichia coli genes encoding putative Na+/H+ exchangers (ycgO) perturbs cytoplasmic alkali cation balance at low osmolarity
    M L Verkhovskaya
    Helsinki Bioenergetics Group, Institute of Biotechnology, PO Box 56 Viikinkaari 5, FIN 00014 University of Helsinki, Finland
    Microbiology 147:3005-13. 2001
    ..Instead, ycgO is required for growth at low osmolarity. Hence it is concluded that ycgO participates in cell volume regulation, and accordingly it is suggested that ycgO be renamed cvrA...
  65. ncbi The Na+ and K+ transport deficiency of an E. coli mutant lacking the NhaA and NhaB proteins is apparent and caused by impaired osmoregulation
    M L Verkhovskaya
    Department of Medical Chemistry, Institute of Biomedical Sciences, University of Helsinki, Finland
    FEBS Lett 439:271-4. 1998
    ..We suggest that this mutant is primarily deficient in osmoregulation rather than in cation transport per se...
  66. pmc Proton exit from the heme-copper oxidase of Escherichia coli
    A Puustinen
    Helsinki Bioenergetics Group, Department of Medical Chemistry, Institute of Biomedical Sciences and Biocentrum Helsinki, P O Box 8, 00014 University of Helsinki, Helsinki, Finland
    Proc Natl Acad Sci U S A 96:35-7. 1999
    ..This may locate the beginning of the pathway by which pumped protons exit from the enzyme structure...
  67. ncbi Charge translocation coupled to electron injection into oxidized cytochrome c oxidase from Paracoccus denitrificans
    M I Verkhovsky
    Department of Medical Chemistry, Institute of Biomedical Sciences and Biocentrum Helsinki, P O Box 8, 00014 University of Helsinki, Helsinki, Finland
    Biochemistry 40:7077-83. 2001
    ..The extent of the electrogenic 135 micrcos phase also rules out the possibility that reduction of the binuclear center by the second electron would be coupled to proton translocation in addition to the electrogenic uptake of a proton...
  68. ncbi The causes of reduced proton-pumping efficiency in type B and C respiratory heme-copper oxidases, and in some mutated variants of type A
    Virve Rauhamäki
    Institute of Biotechnology, University of Helsinki, Viikinkaari 1, 00014 Helsinki, Finland
    Biochim Biophys Acta 1837:999-1003. 2014
    ..This discrepancy might also be explained by a higher sensitivity of proton pumping to protonmotive force in the mutated variant. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference. ..
  69. ncbi Interaction of purified NDH-1 from Escherichia coli with ubiquinone analogues
    Pamela David
    Helsinki Bioenergetics Group, Biotechnology Institute, Biocenter 2, University of Helsinki, Helsinki, Finland
    Biochim Biophys Acta 1553:268-78. 2002
    ..Both ubiquinone-2 and decylubiquinone are good acceptors for this enzyme, while affinity of NDH-1 for ubiquinone-1 is clearly lower than for the other two, particularly in the purified state...
  70. ncbi Structural features of a polypeptide carrier promoting secretion of a beta-lactamase fusion protein in yeast
    E Jämsä
    Institute of Biotechnology, University of Helsinki, Finland
    Yeast 11:1381-91. 1995
    ..The unstructured carrier polypeptide may facilitate proper folding and secretion of heterologous proteins attached to it...
  71. ncbi Electron transfer properties of NADH:ubiquinone reductase in the ND1/3460 and the ND4/11778 mutations of the Leber hereditary optic neuroretinopathy (LHON)
    A Majander
    Department of Medical Chemistry, University of Helsinki, Finland
    FEBS Lett 292:289-92. 1991
    ..This suggests that the ND4 subunit might be involved in specific aggregation of NADH-dependent dehydrogenases and Complex I, which may result in fast ('solid state') electron transfer from the former to the latter...
  72. ncbi Mutations in subunit 6 of the F1F0-ATP synthase cause two entirely different diseases
    A Majander
    Department of Medical Chemistry, Institute of Biomedical Sciences and Biocentrum Helsinki, University of Helsinki, Finland
    FEBS Lett 412:351-4. 1997
    ..Hence, the latter will have much more destructive metabolic consequences in agreement with the large clinical differences between the two diseases...
  73. ncbi Analysis of the pathogenic human mitochondrial mutation ND1/3460, and mutations of strictly conserved residues in its vicinity, using the bacterium Paracoccus denitrificans
    V Zickermann
    Helsinki Bioenergetics Group, Department of Medical Chemistry, University of Helskinki, Finland
    Biochemistry 37:11792-6. 1998
    ..The results suggest that the mutated residues play an important role in ubiquinone reduction by Complex I...
  74. ncbi Partial oxygen pressure and mitochondrial permeability transition affect germ cell apoptosis in the human testis
    K Erkkila
    Hospital for Children and Adolescents, University of Helsinki, Finland
    J Clin Endocrinol Metab 84:4253-9. 1999
    ..The present results imply that to improve germ cell viability in in vitro fertilization techniques, the partial oxygen pressure should be lowered...