Paramagnetic Perturbation of the F-19 NMR Chemical Shift in Fluorinated Cysteine by O-2: A Theoretical Study
2009 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 113, no 31, 10916-10922 p.Article in journal (Refereed) Published
We present a combined molecular dynamics and density functional theory study of dioxygen-induced perturbation of the F-19 NMR chemical shifts in an aqueous solution of fluorinated cysteine under 100 atm of O-2 partial pressure. Molecular dynamics Simulations are carried out to determine the dominant structures of O-2 and the fluorinated cysteine complexes in water, and the collected structural information is exploited in computation of F-19 chemical shifts using density functional theory. The obtained results indicate that the density redistribution of the O-2 unpaired electrons between the dioxygen and fluorinated cysteine is responsible for the experimentally observed perturbation of the F-19 NMR chemical shifts, where the Fermi contact interaction plays the key role. The O-2-induced paramagnetic F-19 chemical shift, averaged over the simulation trajectory, is comparable with the reported experimental values, proving the availability of the developed strategy for modeling F-19 NMR chemical shifts in the presence of paramagnetic agents in ail aqueous solution. The applicability of the combined molecular dynamics/density functional theory approach for dioxygen NMR perturbation to all resonating nuclei including H-1, C-13, N-15, and F-19 is emphasized, and the ramification of this for investigations of membrane protein structures is discussed.
Place, publisher, year, edition, pages
2009. Vol. 113, no 31, 10916-10922 p.
correlated molecular calculations, hyperfine coupling-constants, particle mesh ewald, gaussian-basis sets, solvent exposure, liquid, water, protein-structure, functional theory, immersion depth, dynamics, method
IdentifiersURN: urn:nbn:se:kth:diva-18641DOI: 10.1021/jp902659sISI: 000268479000046ScopusID: 2-s2.0-68149124047OAI: oai:DiVA.org:kth-18641DiVA: diva2:336688
QC 201005252010-08-052010-08-052011-05-11Bibliographically approved