Chemical shift optimization in multidimensional NMR spectra by AUREMOL-SHIFTOPT

Abstract

A problem often encountered in multidimensional NMR-spectroscopy is that an existing chemical shift list of a protein has to be used to assign an experimental spectrum but does not fit sufficiently well for a safe assignment. A similar problem occurs when temperature or pressure series of n-dimensional spectra are to be evaluated automatically. We have developed two different algorithms, AUREMOL-SHIFTOPT1 and AUREMOL-SHIFTOPT2 that fulfill this task. In the present contribution their performance is analyzed employing a set of simulated and experimental two-dimensional and three-dimensional spectra obtained from three different proteins. A new z-score based on atom and amino acid specific chemical shift distributions is introduced to weight the chemical shift contributions in different dimensions properly.

Automated solvent artifact removal and base plane correction of multidimensional NMR protein spectra by AUREMOL-SSA

“…The simulation is based on a full relaxation matrix approach and includes also T 2 -calculations and J-couplings. Gaussian noise was added corresponding to a signal to noise ratio of approximately 2r for a proton-proton pair in a distance of 0.5 nm as described by Baskaran et al (2009). The resulting time domain data were filtered by exponential multiplication with a line broadening in the two dimensions of 3 Hz and finally the data have been Fourier transformed.…”