Journal article

Authors list: Tietze, D; Sartorius, J; Seth, BK; Herr, K; Heimer, P; Imhof, D; Mollenhauer, D; Buntkowsky, G

Publication year: 2017

Pages: 17194-

Journal: Scientific Reports

Volume number: 7

ISSN: 2045-2322

Open access status: Gold

DOI Link: https://doi.org/10.1038/s41598-017-17446-3

Publisher: Nature Research

Abstract: 

A series of small, catalytically active metallopeptides, which were
derived from the nickel superoxide dismutase (NiSOD) active site were
employed to study the mechanism of superoxide degradation especially
focusing on the role of the axial imidazole ligand. In the literature,
there are contradicting propositions about the catalytic importance of
the N-terminal histidine. Therefore, we studied the stability and
activity of a set of eight NiSOD model peptides, which represent the
major model systems discussed in the literature to date, yet differing
in their length and their Ni-coordination. UV-Vis-coupled stopped-flow
kinetic measurements and mass spectrometry analysis unveiled their high
oxidation sensitivity in the presence of oxygen and superoxide resulting
into a much faster Ni(II)-peptide degradation for the amine/amide
Ni(II) coordination than for the catalytically inactive bis-amidate
Ni(II) coordination. With respect to these results we determined the
catalytic activities for all NiSOD mimics studied herein, which turned
out to be in almost the same range of about 2 × 10⁶ M⁻¹ s⁻¹.
From these experiments, we concluded that the amine/amide Ni(II)
coordination is clearly the key factor for catalytic activity. Finally,
we were able to clarify the role of the N-terminal histidine and to
resolve the contradictory literature propositions, reported in previous
studies.

Harvard Citation style: Tietze, D., Sartorius, J., Seth, B., Herr, K., Heimer, P., Imhof, D., et al. (2017) New insights into the mechanism of nickel superoxide degradation from studies of model peptides, Scientific Reports, 7, p. 17194. https://doi.org/10.1038/s41598-017-17446-3

APA Citation style: Tietze, D., Sartorius, J., Seth, B., Herr, K., Heimer, P., Imhof, D., Mollenhauer, D., & Buntkowsky, G. (2017). New insights into the mechanism of nickel superoxide degradation from studies of model peptides. Scientific Reports. 7, 17194. https://doi.org/10.1038/s41598-017-17446-3