relax: dynamics analysis, model-free analysis, relaxation data, R1 and R2 exponential curve-fitting, steady-state NOE calculation, reduced spectral density mapping, relaxation dispersion, N-state model, frame order dynamics theories, stereochemistry, conformational analysis, organic molecules, proteins, RNA, DNA, sugars, and other biomolecules.
relax: dynamics analysis, model-free analysis, relaxation data, R1 and R2 exponential curve-fitting, steady-state NOE calculation, reduced spectral density mapping, relaxation dispersion, N-state model, frame order dynamics theories, stereochemistry, conformational analysis, organic molecules, proteins, RNA, DNA, sugars, and other biomolecules.

relax - Molecular dynamics by NMR data analysis

Analysis software for: Model-free, NMR relaxation (R1, R2, NOE), reduced spectral density mapping, relaxation dispersion, N-state models, frame order theory.

Program features

A cluster of nuclear magnetic spins

The software relax is a collection of tools and algorithms for studying molecular dynamics by analysing experimentally measured NMR data. It is a NMR-specific numerical computation environment that can be used as a replacement for Mathematica, Maple, Matlab, Maxima, etc.

Literature

The primary references for the program relax are d'Auvergne and Gooley, 2008a and d'Auvergne and Gooley, 2008b.

Other literature related to the improved model-free analysis used within relax, which can nevertheless be applied to other techniques, include model-free model selection (d'Auvergne and Gooley, 2003; Chen et al., 2004), model-free model elimination (d'Auvergne and Gooley, 2006), the theory (d'Auvergne and Gooley, 2007) behind the new model-free optimisation protocol (d'Auvergne and Gooley, 2008b), and the hybridisation of different models (Horne et al., 2007; d'Auvergne and Gooley, 2008b). Most of these details can be found in the PhD thesis of d'Auvergne, 2006.

Model-free and relax

Protein Dynamics - A Study of the Model-free Analysis of NMR Relaxation Data

The reference d'Auvergne, E. J. (2006). Protein dynamics: a study of the model-free analysis of NMR relaxation data. Ph.D. thesis, Biochemistry and Molecular Biology, University of Melbourne coving all of the model-free analysis aspects of relax is also published in paperback book form. It is available from Amazon.com, Barnes & Nobel and many other international and national online book stores. This book is from the academic publisher AkademikerVerlag (previously VDM-Verlag - note this site is only in German).

Supported NMR theories

The following NMR relaxation data analysis techniques are currently supported by relax:

Data analysis tools

The following tools are implemented as modular components to be used by any data analysis technique:

Data visualisation

The results of an analysis, or any data input into relax, can be visualised using a number of programs:

Interfacing with other programs

relax can create the input files, execute in-line, and then read the output of the following programs. These programs can be used as optimisation engines replacing the minimisation algorithms built into relax:

The user interfaces (UIs)

relax can be used through the following UIs:

The primary references for relax and the UIs are d'Auvergne and Gooley, 2008a and d'Auvergne and Gooley, 2008b, whereas the primary reference for the GUI is Bieri et al., 2011.

relax GUI

To start relax with the graphical interface, type:

$ relax -g

Some screenshots of the GUI in action are available.