Related ArticlesPotential bias in NMR relaxation data introduced by peak intensity analysis and curve fitting methods.
J Biomol NMR. 2001 Sep;21(1):1-9
Authors: Viles JH, Duggan BM, Zaborowski E, Schwarzinger S, Huntley JJ, Kroon GJ, Dyson HJ, Wright PE
We present an evaluation of the accuracy and precision of relaxation rates calculated using a variety of methods, applied to data sets obtained for several very different protein systems. We show that common methods of data evaluation, such as the determination of peak heights and peak volumes, may be subject to bias, giving incorrect values for quantities such as R1 and R2. For example, one common method of peak-height determination, using a search routine to obtain the peak-height maximum in successive spectra, may be a source of significant systematic error in the relaxation rate. The alternative use of peak volumes or of a fixed coordinate position for the peak height in successive spectra gives more accurate results, particularly in cases where the signal/noise is low, but these methods have inherent problems of their own. For example, volumes are difficult to quantitate for overlapped peaks. We show that with any method of sampling the peak intensity, the choice of a 2- or 3-parameter equation to fit the exponential relaxation decay curves can dramatically affect both the accuracy and precision of the calculated relaxation rates. In general, a 2-parameter fit of relaxation decay curves is preferable. However, for very low intensity peaks a 3 parameter fit may be more appropriate.
relaxGUI: a new software for fast and simple NMR relaxation data analysis and calculation of ps-ns and μs motion of proteins
relaxGUI: a new software for fast and simple NMR relaxation data analysis and calculation of ps-ns and μs motion of proteins
Abstract Investigation of protein dynamics on the ps-ns and μs-ms timeframes provides detailed insight into the mechanisms of enzymes and the binding properties of proteins. Nuclear magnetic resonance (NMR) is an excellent tool for studying protein dynamics at atomic resolution. Analysis of relaxation data using model-free analysis can be a tedious and time consuming process, which requires good knowledge of scripting procedures. The software relaxGUI was...
nmrlearner
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06-06-2011 12:53 AM
relaxGUI: a new software for fast and simple NMR relaxation data analysis and calculation of ps-ns and ?s motion of proteins.
relaxGUI: a new software for fast and simple NMR relaxation data analysis and calculation of ps-ns and ?s motion of proteins.
relaxGUI: a new software for fast and simple NMR relaxation data analysis and calculation of ps-ns and ?s motion of proteins.
J Biomol NMR. 2011 May 27;
Authors: Bieri M, d'Auvergne EJ, Gooley PR
Investigation of protein dynamics on the ps-ns and ?s-ms timeframes provides detailed insight into the mechanisms of enzymes and the binding properties of proteins. Nuclear magnetic resonance (NMR) is an excellent tool for studying...
nmrlearner
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05-28-2011 06:50 PM
[NMR paper] Analysis of slow interdomain motion of macromolecules using NMR relaxation data.
Analysis of slow interdomain motion of macromolecules using NMR relaxation data.
Related Articles Analysis of slow interdomain motion of macromolecules using NMR relaxation data.
J Am Chem Soc. 2001 May 2;123(17):3953-9
Authors: Baber JL, Szabo A, Tjandra N
The interpretation of NMR relaxation data for macromolecules possessing slow interdomain motions is considered. It is shown how the "extended model-free approach" can be used to analyze (15)N backbone relaxation data acquired at three different field strengths for Xenopus Ca(2+)-ligated...
[Question from NMRWiki Q&A forum] What software can copy peak assignments for 2D T1 and T2 relaxation rate data analysi
What software can copy peak assignments for 2D T1 and T2 relaxation rate data analysis?
Hello,
I'm currently processing a large amount of T1 and T2 spectra in NMRDraw. I've been looking for a way to copy my peak assignments from one spectrum onto to the others so that I can quickly and accurately match height and volume values, but I've had little luck so far. Is it possible to manipulate the assignment tables to achieve this goal? NMRPipe and its associated applications are all very new to me at this point, so any information that may expand my general knowledge of the program or...
nmrlearner
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08-22-2010 02:30 AM
[NMR paper] Assessing potential bias in the determination of rotational correlation times of prot
Assessing potential bias in the determination of rotational correlation times of proteins by NMR relaxation.
Related Articles Assessing potential bias in the determination of rotational correlation times of proteins by NMR relaxation.
J Biomol NMR. 1999 Feb;13(2):101-12
Authors: Lee AL, Wand AJ
The various factors that influence the reliable and efficient determination of the correlation time describing molecular reorientation of proteins by NMR relaxation methods are examined. Nuclear Overhauser effects, spin-lattice, and spin-spin relaxation...
nmrlearner
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08-21-2010 04:03 PM
peak intensity vs number of scans
Hi,
I have a question regarding how the peak intensities change when with increase in number of scans when the data is collected on a Varian NMR spectrometer. Suppose I collect a 15N-1H HSQC spectra with 8 scans and then collect the same spectra with 16 scans, would the peak intensities be double in the 16 scan spectra as compared to the 8 scan spectra? Does anyone know how the varian spectrometer scales the intensities according to the number of scans? Any suggestion or reply to my query will be extremely useful and greatly appreciated.
Thanks.
aish1982
NMR software
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08-08-2008 11:56 PM
peak intensity vs number of scans
Hi,
I have a question regarding how the peak intensities change when with increase in number of scans when the data is collected on a Varian NMR spectrometer. Suppose I collect a 15N-1H HSQC spectra with 8 scans and then collect the same spectra with 16 scans, would the peak intensities be double in the 16 scan spectra as compared to the 8 scan spectra? Does anyone know how the varian spectrometer scales the intensities according to the number of scans? Any suggestion or reply to my query will be extremely useful and greatly appreciated.
Thanks.