Simulations of polyglutamic and polyaspartic oligopeptides of 32 amino acids in solution with counterions

Simulations of polyglutamic and polyaspartic oligopeptides of 32 amino acids in solution with only counterions (Na+ or K+). For each oligopeptide we have simulated: Charmm36 - "c" using either K+ and Na+ original counterions Charmm36 (scaled version) - "sc" using either K_s or NA_s scaled counterions Amber99sb-ildn - "a" using either K+ and Na+ original counterions Amber99sb-ildn (scaled version) - "sa" - using either K_s or NA_s scaled counterions Scaled counterions can be found in https://bitbucket.org/hseara/ions/ Amber99sb-ildn oligopeptides: 32 aminoacids (ASP or GLU) with ACE in the N-terminal and COO- in the C-terminal. Charmm36 oligopeptides: 32 amino acids (ASP or GLU) with NH2 in the N-Terminal and COO- in the C-terminal. MD engine: gromacs 2018 or 2018.3 Temperature: 300 K Pressure: 1 bar Simulation time: 1000 ns Saving frequency: 100 ps