Related ArticlesEffects of structural differences on the NMR chemical shifts in isostructural dipeptides.
J Phys Chem A. 2014 Apr 10;118(14):2618-28
Authors: Altheimer BD, Mehta MA
Abstract
Porous crystalline dipeptides have gained recent attention for their potential as gas-storage materials. Within this large class is a group of dipeptides containing alanine, valine, and isoleucine with very similar crystal structures. We report the (13)C (carbonyl and C?) and (15)N (amine and amide) solid-state NMR isotropic chemical shifts in a series of seven such isostructural porous dipeptides as well as shift tensor data for the carbonyl and amide sites. Using their known crystal structures and aided by ab initio quantum chemical calculations for the resonance assignments, we elucidate trends relating local structure, hydrogen-bonding patterns, and chemical shift. We find good correlation between the backbone dihedral angles and the C?1 and C?2 shifts. For the C1 shift tensor, the ?11 value shifts downfield as the hydrogen-bond distance increases, ?22 shifts upfield, and ?33 shows little variation. The C2 shift tensor shows no appreciable correlation with structural parameters. For the N2 tensor, ?11 shows little dependence on the hydrogen-bond length, whereas ?22 and ?33 both show a decrease in shielding as the hydrogen bond shortens. Our analysis teases apart some, but not all, structural contributors to the observed differences the solid-state NMR chemical shifts.
Interpreting Protein Structural Dynamics from NMR Chemical Shifts
Interpreting Protein Structural Dynamics from NMR Chemical Shifts
Paul Robustelli, Kate A. Stafford and Arthur G. Palmer
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja300265w/aop/images/medium/ja-2012-00265w_0003.gif
Journal of the American Chemical Society
DOI: 10.1021/ja300265w
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/AvG321E_RMU
[NMR paper] Secondary structural effects on protein NMR chemical shifts.
Secondary structural effects on protein NMR chemical shifts.
Related Articles Secondary structural effects on protein NMR chemical shifts.
J Biomol NMR. 2004 Nov;30(3):233-44
Authors: Wang Y
For an amino acid in protein, its chemical shift, delta(phi, psi)(s), is expressed as a function of its backbone torsion angles (phi and psi) and secondary state (s): delta(phi, psi)(s=deltaphi, psi)_coil+Deltadelta(phi, psi)_s), where delta(phi, psi)(coil) represents its chemical shift at coil state (s=coil); Delta delta(phi, psi)(s) (s=sheet or helix) is...
nmrlearner
Journal club
0
11-24-2010 10:03 PM
[NMR paper] Secondary and tertiary structural effects on protein NMR chemical shifts: an ab initi
Secondary and tertiary structural effects on protein NMR chemical shifts: an ab initio approach.
Related Articles Secondary and tertiary structural effects on protein NMR chemical shifts: an ab initio approach.
Science. 1993 Jun 4;260(5113):1491-6
Authors: de Dios AC, Pearson JG, Oldfield E
Recent theoretical developments permit the prediction of 1H, 13C, 15N, and 19F nuclear magnetic resonance chemical shifts in proteins and offer new ways of analyzing secondary and tertiary structure as well as for probing protein electrostatics. For 13C,...
nmrlearner
Journal club
0
08-21-2010 11:53 PM
Use of chemical shifts for structural studies of nucleic acids
Use of chemical shifts for structural studies of nucleic acids
Publication year: 2010
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, In Press, Accepted Manuscript, Available online 1 February 2010</br>
Sik Lok, Lam , Lai Man, Chi</br>
More...
nmrlearner
Journal club
0
08-16-2010 03:50 AM
Mapping of protein structural ensembles by chemical shifts
Abstract Applying the chemical shift prediction programs SHIFTX and SHIFTS to a data base of protein structures with known chemical shifts we show that the averaged chemical shifts predicted from the structural ensembles explain better the experimental data than the lowest energy structures. This is in agreement with the fact that proteins in solution occur in multiple conformational states in fast exchange on the chemical shift time scale. However, in contrast to the real conditions in solution at ambient temperatures, the standard NMR structural calculation methods as well chemical shift...
nmrlearner
Journal club
0
08-14-2010 04:19 AM
Sequential nearest-neighbor effects on computed 13Cα chemical shifts
Abstract To evaluate sequential nearest-neighbor effects on quantum-chemical calculations of 13Cα chemical shifts, we selected the structure of the nucleic acid binding (NAB) protein from the SARS coronavirus determined by NMR in solution (PDB id 2K87). NAB is a 116-residue α/β protein, which contains 9 prolines and has 50% of its residues located in loops and turns. Overall, the results presented here show that sizeable nearest-neighbor effects are seen only for residues preceding proline, where Pro introduces an overestimation, on average, of 1.73 ppm in the computed 13Cα chemical...
nmrlearner
Journal club
0
08-14-2010 04:19 AM
Density functional calculations of 15N chemical shifts in solvated dipeptides
Density functional calculations of 15N chemical shifts in solvated dipeptides
Ling Cai, David Fushman and Daniel S. Kosov
Journal of Biomolecular NMR; 2008; 41(2) pp 77 - 88
Abstract:
We performed density functional calculations to examine the effects of solvation, hydrogen bonding, backbone conformation, and the side chain on 15N chemical shielding in proteins. We used N-methylacetamide (NMA) and N-formyl-alanyl-X (with X being one of the 19 naturally occurring amino acids excluding proline) as model systems. In addition, calculations were performed for selected fragments from...
Effects of structural differences on the NMR chemical shifts in isostructural dipeptides.
Linear Mode
