Jump to main content
Jump to site search

Issue 44, 2016
Previous Article Next Article

RIDME spectroscopy on high-spin Mn2+ centers

Author affiliations

Abstract

Pulsed EPR dipolar spectroscopy is a powerful tool for determining the structure and conformational dynamics of biological macromolecules, as it allows precise measurements of distances in the range of 1.5–10 nm. Utilization of high-spin Mn2+ species as spin probes for distance measurements is of significant interest, because they are biologically compatible and endogenous in numerous biological systems. However, to date dipolar spectroscopy experiments with this kind of species have been underexplored. Here we present pulsed electron electron double resonance (PELDOR also called DEER) and relaxation-induced dipolar modulation enhancement (RIDME) experiments, which have been performed at W-band (94 GHz) and J-band frequencies (263 GHz) on a bis-MnDOTA (DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate) model system. The distances obtained from these experiments are in good agreement with predictions. RIDME experiments reveal a significantly higher modulation depth compared to PELDOR, which is an important consideration for biological samples. These experiments also feature higher harmonics of the dipolar coupling frequency due to effective multiple-quantum relaxation of high-spin Mn2+ as well as the multiple-component background function. Harmonics of the dipolar coupling frequency were taken into account by including additional terms in the kernel function of Tikhonov regularization analysis.

Graphical abstract: RIDME spectroscopy on high-spin Mn2+ centers

Back to tab navigation

Supplementary files

Publication details

The article was received on 28 Jul 2016, accepted on 05 Oct 2016 and first published on 13 Oct 2016


Article type: Paper
DOI: 10.1039/C6CP05239H
Citation: Phys. Chem. Chem. Phys., 2016,18, 30857-30866
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    RIDME spectroscopy on high-spin Mn2+ centers

    D. Akhmetzyanov, H. Y. V. Ching, V. Denysenkov, P. Demay-Drouhard, H. C. Bertrand, L. C. Tabares, C. Policar, T. F. Prisner and S. Un, Phys. Chem. Chem. Phys., 2016, 18, 30857
    DOI: 10.1039/C6CP05239H

Search articles by author

Spotlight

Advertisements