January 2012
Publication year: 2012 Source:Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 60
The exquisite sensitivity of chemical shifts as reporters of structural information, and the ability to measure them routinely and accurately, gives great import to formulations that elucidate the structure-chemical-shift relationship. Here we present a new and highly accurate, precise, and robust formulation for the prediction of NMR chemical shifts from protein structures. Our approach, shAIC (shift prediction guided by Akaikes Information Criterion), capitalizes on mathematical ideas and an information-theoretic principle, to represent the functional form of the relationship between structure and chemical shift as a parsimonious sum of smooth analytical potentials which optimally takes into account short-, medium-, and long-range parameters in a nuclei-specific manner to capture potential chemical shift perturbations caused by distant nuclei. shAIC outperforms the state-of-the-art methods that use analytical formulations. Moreover, for structures derived by NMR or structures with novel folds, shAIC delivers better overall results; even when it is compared to sophisticated machine learning approaches. shAIC provides for a computationally lightweight implementation that is unimpeded by molecular size, making it an ideal for use as a force field. Graphical abstract
Highlights
shAIC predicts chemical shifts accurately for proteins based on their structure using a statistical approach summing local and long-range contributions applying Akaikes Information Criterion to optimally parameterize the method. ? We present a new method, shAIC, for predicting protein chemical shift based on the structure. ? shAIC is a statistical approach using a sum of analytical, smooth, differential potentials. ? shAIC uses Akaikes Information Criterion to optimally parameterize the method. ? shAIC is equally or more accurate than other methods. ? shAIC uses novel structural parameters of medium and long range.
PPM: a side-chain and backbone chemical shift predictor for the assessment of protein conformational ensembles
PPM: a side-chain and backbone chemical shift predictor for the assessment of protein conformational ensembles
Abstract The combination of the wide availability of protein backbone and side-chain NMR chemical shifts with advances in understanding of their relationship to protein structure makes these parameters useful for the assessment of structural-dynamic protein models. A new chemical shift predictor (PPM) is introduced, which is solely based on physicalâ??chemical contributions to the chemical shifts for both the protein backbone and methyl-bearing amino-acid side chains. To...
nmrlearner
Journal club
0
09-15-2012 09:04 AM
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Publication year: 2012
Source:Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 60</br>
Jakob T. Nielsen, Hamid R. Eghbalnia, Niels Chr. Nielsen</br>
The exquisite sensitivity of chemical shifts as reporters of structural information, and the ability to measure them routinely and accurately, gives great import to formulations that elucidate the structure-chemical-shift relationship. Here we present a new and highly accurate, precise,...
nmrlearner
Journal club
0
03-09-2012 09:16 AM
Combining NMR ensembles and molecular dynamics simulations provides more realistic models of protein structures in solution and leads to better chemical shift prediction
Combining NMR ensembles and molecular dynamics simulations provides more realistic models of protein structures in solution and leads to better chemical shift prediction
Abstract While chemical shifts are invaluable for obtaining structural information from proteins, they also offer one of the rare ways to obtain information about protein dynamics. A necessary tool in transforming chemical shifts into structural and dynamic information is chemical shift prediction. In our previous work we developed a method for 4D prediction of protein 1H chemical shifts in which molecular motions, the...
nmrlearner
Journal club
0
02-11-2012 10:31 AM
SHIFTX2: Chemical Shift Prediction
SHIFTX2 website
SHIFTX2 is capable of rapidly and accurately calculating diamagnetic 1H, 13C and 15N chemical shifts from protein coordinate data. Compared to its predecessor (SHIFTX) and to other existing protein chemical shift prediction programs, SHIFTX2 is substantially more accurate (up to 26% better by correlation coefficient with an RMS error that is up to 3.3× smaller) than the next best performing program. It also provides significantly more coverage (up to 10% more), is significantly faster (up to 8.5×) and capable of calculating a wider variety of backbone and side chain...
gwnmr
NMR software
0
01-10-2012 06:13 PM
Calculation of chemical shift anisotropy in proteins
Calculation of chemical shift anisotropy in proteins
Abstract Individual peptide groups in proteins must exhibit some variation in the chemical shift anisotropy (CSA) of their constituent atoms, but not much is known about the extent or origins of this dispersion. Direct spectroscopic measurement of CSA remains technically challenging, and theoretical methods can help to overcome these limitations by estimating shielding tensors for arbitrary structures. Here we use an automated fragmentation quantum mechanics/molecular mechanics (AF-QM/MM) approach to compute 15N, 13Câ?² and 1H...
nmrlearner
Journal club
0
08-29-2011 06:41 AM
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Publication year: 2011
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, In Press, Accepted Manuscript, Available online 23 May 2011</br>
Jakob T., Nielsen , Hamid R., Eghbalnia , Niels Chr., Nielsen</br>
The exquisite sensitivity of chemical shifts as reporters of structural information, and the ability to measure them routinely and accurately, gives great import to formulations that elucidate the structure-chemical-shift relationship. Here we...
nmrlearner
Journal club
0
05-24-2011 10:02 PM
SHIFTX2: significantly improved protein chemical shift prediction
SHIFTX2: significantly improved protein chemical shift prediction
Abstract A new computer program, called SHIFTX2, is described which is capable of rapidly and accurately calculating diamagnetic 1H, 13C and 15N chemical shifts from protein coordinate data. Compared to its predecessor (SHIFTX) and to other existing protein chemical shift prediction programs, SHIFTX2 is substantially more accurate (up to 26% better by correlation coefficient with an RMS error that is up to 3.3Ã? smaller) than the next best performing program. It also provides significantly more coverage (up to 10% more),...
nmrlearner
Journal club
0
04-01-2011 09:31 PM
Protein secondary structure prediction using NMR chemical shift data.
Protein secondary structure prediction using NMR chemical shift data.
Related Articles Protein secondary structure prediction using NMR chemical shift data.
J Bioinform Comput Biol. 2010 Oct;8(5):867-84
Authors: Zhao Y, Alipanahi B, Li SC, Li M
Accurate determination of protein secondary structure from the chemical shift information is a key step for NMR tertiary structure determination. Relatively few work has been done on this subject. There needs to be a systematic investigation of algorithms that are (a) robust for large datasets; (b)...