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AMBER (Assisted Model Building with Energy Refinement) refers to two things: a set of molecular mechanical force fields for the simulation of biomolecules (which are in the public domain, and are used in a variety of simulation programs); and a package of molecular simulation programs which includes source code and demos. The current version of the code is AMBER version 7. The release consists of about 60 programs, that work reasonably well together. The major programs are as follows: * sander: Simulated annealing with NMR-derived energy restraints. This allows for NMR refinement based on NOE-derived distance restraints, torsion angle restraints, and penalty functions based on chemical shifts and NOESY volumes. Sander is also the "main" program used for molecular dynamics simulations. * gibbs: This program includes free energy perturbation (FEP) and thermodynamic integration (TI) [window growth, slow growth, and dynamically modified windows], and also allows potential of mean force (PMF) calculations. * roar: This module was contributed by Ken Merz' group at Penn State. It allows mixed quantum-mechanical/molecular-mechanical (QM/MM) calculations, "true" Ewald simulations, and alternate molecular dynamics integrators. * nmode: Normal mode analysis program using first and second derivative information, used to find search for local minima, perform vibrational analysis, and search for transition states. * LEaP: LEaP is an X-windows-based program that provides for basic model building and AMBER coordinate and parameter/topology input file creation. It includes a molecular editor which allows for building residues and manipulating molecules. Example xleap windows (40Kbytes of gifs). Motif-style X-windows Athena widgets and a table widget used in LEaP were written by Vladimir Romanovski. * antechamber: This program suite automates the process of developing force field descriptors for most organic molecules. It starts with structures (usually in PDB format), and generates files that can be read into LEaP for use in molecular modeling. The force field description that is generated is designed to be compatible with the usual Amber force fields for proteins and nucleic acids. * ptraj and carnal: These are programs to analyze MD trajectories, computing a variety of things, like RMS deviation from a reference structure, hydrogen bonding analysis, time-correlation functions, diffusional behavior, and so on. * mm_pbsa: This is a script to automate post-processing of MD trajectories, to analyze energetics using continuum solvent ideas. It can be used to break energies energies into "pieces" arising from different residues, and to estimate free energy differences between conformational basins. AMBER runs on Linux machines s; the executable is in: /joule2/programs/AMBER/c28b2/exec/gnu/AMBER or just type "AMBER" The local documentation is in: /joule2/programs/amber/amber7/doc/amber7.pdf or from the author's web site at http://amber.scripps.edu/ also see tutorials: http://amber.scripps.edu/tutorial/index.html NOTES FROM MIKE: The executables will run on Linux computers. Just type the name of the executable. Note1: We have the text only version of Leap, not the x-windows based version. The x-windows version does not compile on our Linux machines. Note2: Antechamber will not run because we lack the program MOPAC. MOPAC costs $2000. | ||||||||