A 95 GHz pulsed deuterium ENDOR study has been performed on single crystals of azurin from Pseudomonas aeruginosa selectively deuterated at the C(beta) position of the copper-coordinating cysteine 112. Complete hyperfine tensors of the two deuterium atoms have been obtained, which reveal identical isotropic parts. Analysis of the hyperfine tensors provides insight into the spin-density delocalization over the cysteine ligand. Approximately 45 % of the spin density in the paramagnetic site can be attributed to copper and 30 % to sulfur.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/cphc.200500551 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Cu(II) Stability and UV-Induced Electron Transfer in a Metal-Organic Hybrid: An EPR, DFT, and Crystallographic Characterization of Copper-Doped Zinc Creatininium Sulfate.
J Phys Chem A
December 2024
Department of Physics and Department of Biological, Geological and Environmental Sciences, Cleveland State University, Cleveland, Ohio 44115, United States.
Single-crystal X-ray diffraction and electron paramagnetic resonance (EPR) spectroscopic experiments, complemented by quantum chemical DFT calculations, were carried out on the copper-doped metal-organic hybrid and Tutton salt analogue zinc creatininium sulfate to determine its crystal structure, to characterize the electronic structure of the doped Cu(II) binding site, and to propose a pathway for an excited-state, proton-coupled electron transfer (PCET) process in UV-exposed crystals. The crystal structure is isomorphous to that of cadmium creatininium sulfate, which has the transition ion, not in direct coordination with the creatinine, but forming a hexahydrate complex, which is bridged to a creatininium through an intervening sulfate ion. The EPR (2.
View Article and Find Full Text PDFRepeatability of diffusion kurtosis tensor parameters in muscles of the lower legs.
Magn Reson Med
March 2025
Cancer Systems Imaging, MD Anderson Cancer Center, Houston, Texas, USA.
Purpose: The aim of this study was to provide measurements from and investigate the repeatability of diffusion kurtosis tensor parameters in the muscles of the lower legs.
Methods: Test-retest acquisition of a kurtosis tensor sequence was performed in 13 healthy volunteers. Quantitative kurtosis tensor parameters were derived, and repeatability of each parameter was evaluated by muscle group and over the whole muscle through intraclass correlation coefficient (ICC) and within-subject coefficient of variation (wsCV).
Insights of the peroxychloroformyl radical ClC(O)OO microwave spectrum.
Phys Chem Chem Phys
November 2024
Department of Applied Chemistry, Science Building II, National Yang Ming Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu 30093, Taiwan.
The exploration of Venus has received much attention in the past and will keep growing due to the starting of the NASA DAVINCI project. To explain the extremely low O : CO ratio observed in Venus' atmosphere, a chlorine-initiated CO oxidation catalytic cycle has been proposed. However, relevant studies on the key intermediates, such as the peroxychloroformyl radical (ClC(O)OO), are rare.
View Article and Find Full Text PDFMolecular influence on nuclear-quadrupole-coupling effects in laser induced alignment.
J Chem Phys
September 2024
Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
We computationally studied the effect of nuclear-quadrupole interactions on the field-free impulsive alignment of different asymmetric-top molecules. Our analysis is focused on the influence of the hyperfine- and rotational-energy-level structures. These depend on the number of nuclear spins, the rotational constants, and the symmetry of the tensors involved in the nuclear spin and external field interactions.
View Article and Find Full Text PDFElectric Field Dependence of EPR Hyperfine Coupling Constants.
J Phys Chem A
September 2024
Institute of Chemistry, University of Silesia in Katowice, Szkolna 9, 40-006 Katowice, Poland.
In this article, we introduce a simple but reliable method to calculate the electric field dependence of the isotropic hyperfine coupling tensor for free radicals. This dependence, also referred to as the Bloembergen effect, can be of interest in analyzing EPR experiments for solid-state materials but is rarely studied for isolated radicals in the gaseous phase. The proposed method uses the numerical differentiation of the field-perturbed tensor and, consequently, as a purely numerical method, does not depend on a quantum chemical method used to determine the hyperfine tensor .
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!