Computational evidence support the hypothesis of neuroglobin also acting as an electron transfer species

  • Licia Paltrinieri
  • Giulia Di Rocco
  • Gianantonio Battistuzzi
  • Marco Borsari
  • Marco Sola
  • Antonio Ranieri
  • Laura Zanetti-Polzi
  • Isabella Daidone
  • Carlo Augusto Bortolotti
Original Paper


Neuroglobin (Ngb) is a recently identified hexa-coordinated globin, expressed in the nervous system of humans. Its physiological role is still debated: one hypothesis is that Ngb serves as an electron transfer (ET) species, possibly by reducing cytochrome c and preventing it to initiate the apoptotic cascade. Here, we use the perturbed matrix method (PMM), a mixed quantum mechanics/molecular dynamics approach, to investigate the redox thermodynamics of two neuroglobins, namely the human Ngb and GLB-6 from invertebrate Caenorhabditis elegans. In particular, we calculate the reduction potential of the two globins, resulting in an excellent agreement with the experimental values, and we predict the reorganization energies, λ, which have not been determined experimentally yet. The calculated λ values match well those reported for known ET proteins and thereby support a potential involvement in vivo of the two globins in ET processes.


Hexa-coordinated globins Reorganization energy Molecular dynamics simulation Cytochrome c Reduction potential Thermodynamics 

Supplementary material

775_2017_1455_MOESM1_ESM.pdf (1.1 mb)
Supplementary Material Details on the quantum chemical calculations and on the theoretical methods for the estimation of the reduction potential; First eigenvector components for GLB-6 and Ngb (PDF 1178 kb)


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Copyright information

© SBIC 2017

Authors and Affiliations

  • Licia Paltrinieri
    • 1
  • Giulia Di Rocco
    • 1
  • Gianantonio Battistuzzi
    • 2
  • Marco Borsari
    • 2
  • Marco Sola
    • 1
  • Antonio Ranieri
    • 1
  • Laura Zanetti-Polzi
    • 3
  • Isabella Daidone
    • 3
  • Carlo Augusto Bortolotti
    • 1
    • 4
  1. 1.Department of Life SciencesUniversity of Modena and Reggio EmiliaModenaItaly
  2. 2.Department of Chemical and Geological SciencesUniversity of Modena and Reggio EmiliaModenaItaly
  3. 3.Department of Physical and Chemical SciencesUniversity of L’AquilaL’AquilaItaly
  4. 4.Center S3, CNR NANO, Institute of NanoscienceModenaItaly

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