gromacs软件包top文件夹下:7种 amber94 amberGS.ffamber96 amber99amber99sbamber99sb-ildn amber03 各个版本: http://ffamber.cnsm.csulb.edu/ffamber.php amber94 就是 jacs1995 文章的参数。 AMBER-96 is a variant of AMBER-94 in which peptide f/y torsional potentials have been adjusted to yeild better agreement between molecular mechanical and quantum mechanical energetics (disfavoring helices, favoring extended conformations). AMBER-GS is identical to AMBER-94 with peptide f/y torsional potentials removed (set to zero). 这里说了, In our ff99SB paper we cite and discuss it, and show that it has some not very good properties. http://archive.ambermd.org/201203/0517.html AMBER-99 is the 3rd generation update to AMBER-94(2 nd generation), including updated parameters for both amino and nucleic acids. The primary changes for peptides/proteins is again in the f/y torsional potentials (again to disfavor helical conformations). 所以可以放弃 amber94, amber96 了。 AMBER-99SB is the AMBER-99 variant developed by Simmerling and co-workers with updated backbone f/y torsions fit to ab initio calculations. 第三方修正的。 AMBER-03 is a variant of the AMBER-99 potential in which charges and main-chain torsion potentials have been rederived based on QM+ continuum solvent calculations and each amino acid is allowed unique main-chain charges. 也就是 amber99 的官方修正版。( 注意 : Instead of relying on the HF/6-31G* approach to provide aqueous-phase charges, a low-dielectric continuum model corresponding to an organic solvent environment was included directly in the QM calculation of the dihedral parameters and electrostatic potential (from which the charges are obtained). Because of these differences, ff03 should be considered a distinct force field model rather than extension of previous Amber force fields ) amber99sb-ildn 针对 I,L,D,N 四种氨基酸的优化: 被2010年 science 文章引用: Atomic-Level Characterization of the Structural Dynamics of Proteins ( tip3p water )因此倾向于采用 amber99sb-ildn 。 最新的是amber ff14sb力场: https://pubs.acs.org/doi/pdf/10.1021/acs.jctc.5b00255 ff14sb 仍然是用的 tip3p water model 力场,说明 tip3p 还是可以继续用的。此外, ff14sb 目前已经推荐,但 gromacs 力场 package 里还没有默认 include 进来,而 ff99sb-ildn 也已经足够好 。 关于 ff99SB* 和 ff03* 力场, proposed in this paper: https://pubs.acs.org/doi/pdf/10.1021/jp901540t 该力场知名度一般,升级版 ff99SB*-ildn 在 D.E.Shaw 的文章里第一次提,详细讨论见: http://archive.ambermd.org/201409/0260.html 此外, Review article 说: the force fields that are capable of reversibly folding globular proteins such as AMBER99sb with * and/or ILDN 165c modifications and CHARMM22* 166 in the studies described in refs 170b and 170d may not necessarily be the most suitable for characterizing the metastable states of disordered ensembles. (其实这里不包括 amber99sb-ildn,170b 是 amber99sb*-ildn , 170d 是 charmm22*。 )
Download AmberTools15: http://ambermd.org/AmberTools15-get.html before installing, you need these packages: sudo apt-get install csh flex patch gfortran g++ make xorg-dev bison libbz2-dev sudo apt-get install python-tk python-dev python-matplotlib python-numpy python-scipy sudo apt-get install libboost-python-dev Install Amber: cd /home/myname/install tar xvfj AmberTools15.tar.bz2 cd amber14 export AMBERHOME /home/myname/install/amber14 cd $AMBERHOME ./configure -gnu make install make test