Pressure-dependent 13C chemical shifts in proteins: origins and applications.

Pressure-dependent C chemical shifts in proteins: Origins and applications

A New Development of Electronic Descriptors for Simulation of 13C Chemical Shifts

The 13C chemical shifts for a series of compounds which includes carboxylic acids, aldehydes, ethers, ketones and hydrocarbons were simulated by using the parametric techniques. The observed chemical shifts were related to numerically encoded structural parametes called descriptors. Two new electronic descriptors were added to the previous descriptors. Ploting of experimental ver...

Ab Initio Quantum Chemical Studies of 15N and 13C NMR Shielding Tensors in Serine and Complexes of Serine- nH2O: Investigation on Strength of the CαH…O Hydrogen bonding in the Amino Acid Residue.

In this paper, the hydrogen bonding (HB) effects on the NMR chemical shifts of selected atoms in serineand serine-nH2O complexes (from one to ten water molecules) have been investigated with quantummechanical calculations of the 15N and 13C tensors. Interaction with water molecules causes importantchanges in geometry and electronic structure of serine.For the compound studied, the most importan...

The Conformational Effect of 6-Mono-Substituted and 6,7-Di-Substituted Derivatives of 5,6,7,8-Tetrahydrodibenzo[a,c]cyclo-octene on 13C Chemical Shift

Hartree-Fock (HF) and Density Functional Theory (DFT) methods employed to study the effect of conformational change on the 13C chemical shifts of 6-mono axial and equatorial substituted and 6,7-di axial-axial, equatorial-equatorial and axial-equatorial substitutedderivatives of 5,6,7,8-tetrahydrodibenzo[a,c]cyclo-octene. The geometry of the conformers have been optimized...

Structure of an elastin-mimetic polypeptide by solid-state NMR chemical shift analysis.

The conformation of an elastin-mimetic recombinant protein, [(VPGVG)4(VPGKG)]39, is investigated using solid-state NMR spectroscopy. The protein is extensively labeled with 13C and 15N, and two-dimensional 13C-13C and 15N-13C correlation experiments were carried out to resolve and assign the isotropic chemical shifts of the various sites. The Pro 15N, 13Calpha, and 13Cbeta isotropic shifts, and...