[gmx-users] multiple ligands topology

Jennifer Vo quyviolet at gmail.com
Fri Feb 13 15:59:34 CET 2015


Dear Justin,
Many thanks for your kind answer. The output of minimization for Protein +
1 Ligand
Steepest Descents converged to Fmax < 100 in 868 steps
Potential Energy  = -8.0409740e+06
Maximum force     =  8.3073639e+01 on atom 267747
Norm of force     =  3.5544858e+00

The out for Protein + 2 ligands
Steepest Descents converged to Fmax < 100 in 2165 steps
Potential Energy  = -6.2125650e+06
Maximum force     =  8.6047729e+01 on atom 263858
Norm of force     =  3.6529241e+00

I don't see any failure. But when I use trjconv from Output gro file to pdb
file, I see the ligands screwed up.
In case "The ligand files are both set up within different boxes, so
perhaps the construction of your system is incorrect somehow", how do I fix
it? Do I have to change the final line of every ligand's topology file?
Which are

1IR3    HAF   22  10.581  10.138  10.385
20.72517  20.72517  20.72517
and
    1NPD    H8A   73  -0.376   0.292  -5.440
   1.94588     0.88647     1.08377

and the box of the System including Proteins + 2 ligands

23746NA      NA79296  15.582  10.741   1.636
  15.63000  15.63000  15.63000

Many thanks in advance!
Jennifer


On Fri, Feb 13, 2015 at 3:44 PM, Justin Lemkul <jalemkul at vt.edu> wrote:

>
>
> On 2/13/15 6:03 AM, Jennifer Vo wrote:
>
>> Dear All,
>> I am running a simulation for a systems including two chains of proteins
>> and two ligands using amber 99SB ff.
>> My topol.top is
>>
>> #include "amber99sb.ff/forcefield.itp"
>> #include "my_ligand_atomtypes.itp"
>>
>> ; Include chain topologies
>> #include "A.itp"
>> #ifdef POSRES
>> #include "posre_A.itp"
>> #endif
>> #include "B.itp"
>> #ifdef POSRES
>> #include "posre_B.itp"
>> #endif
>>
>> ; Include custom ligand topologies
>> #include "npd.itp"
>> #ifdef POSRES_LIG
>> #include "posre_npd.itp"
>> #endif
>> ; Include custom ligand topologies
>> #include "ir3_em.itp"
>> ; Include water topology
>> #include "amber99sb.ff/tip3p.itp"
>>
>> #ifdef POSRES_WATER
>> ; Position restraint for each water oxygen
>> [ position_restraints ]
>> ;  i funct       fcx        fcy        fcz
>>     1    1       1000       1000       1000
>> #endif
>> ; Include generic ion topology
>> #include "amber99sb.ff/ions.itp"
>>
>> [ system ]
>> ; Name
>> BcSIRED in water
>> [ molecules ]
>> ; Compound        #mols
>> A             1
>> B             1
>> NPD                   1
>> IR3                   9
>> SOL         123406
>> NA               24
>>
>> then I have my_ligand_atomtypes.itp
>> [ atomtypes ]
>> ;name   bond_type     mass     charge   ptype   sigma         epsilon
>> Amb
>>   CA       CA          0.00000  0.00000   A     3.39967e-01   3.59824e-01
>> ;
>> 1.91  0.0860
>>   H4       H4          0.00000  0.00000   A     2.51055e-01   6.27600e-02
>> ;
>> 1.41  0.0150
>>   HA       HA          0.00000  0.00000   A     2.59964e-01   6.27600e-02
>> ;
>> 1.46  0.0150
>>   C        C           0.00000  0.00000   A     3.39967e-01   3.59824e-01
>> ;
>> 1.91  0.0860
>>   O        O           0.00000  0.00000   A     2.95992e-01   8.78640e-01
>> ;
>> 1.66  0.2100
>>   N        N           0.00000  0.00000   A     3.25000e-01   7.11280e-01
>> ;
>> 1.82  0.1700
>>   H        H           0.00000  0.00000   A     1.06908e-01   6.56888e-02
>> ;
>> 0.60 0.0157
>>   N*       N*          0.00000  0.00000   A     3.25000e-01   7.11280e-01
>> ;
>> 1.82  0.1700
>>   CT       CT          0.00000  0.00000   A     3.39967e-01   4.57730e-01
>> ;
>> 1.91  0.1094
>>   H2       H2          0.00000  0.00000   A     2.29317e-01   6.56888e-02
>> ;
>> 1.29  0.0157
>>   H1       H1          0.00000  0.00000   A     2.47135e-01   6.56888e-02
>> ;
>> 1.39  0.0157
>>   OH       OH          0.00000  0.00000   A     3.06647e-01   8.80314e-01
>> ;
>> 1.72  0.2104
>>   HO       HO          0.00000  0.00000   A     0.00000e+00   0.00000e+00
>> ;
>> 0.00  0.0000
>>   OS       OS          0.00000  0.00000   A     3.00001e-01   7.11280e-01
>> ;
>> 1.68 0.1700
>>   P        P           0.00000  0.00000   A     3.74177e-01   8.36800e-01
>> ;
>> 2.10  0.2000
>>   O2       O2          0.00000  0.00000   A     2.95992e-01   8.78640e-01
>> ;
>> 1.66  0.2100
>>   CK       CK          0.00000  0.00000   A     3.39967e-01   3.59824e-01
>> ;
>> 1.91  0.0860
>>   H5       H5          0.00000  0.00000   A     2.42146e-01   6.27600e-02
>> ;
>> 1.36  0.0150
>>   NB       NB          0.00000  0.00000   A     3.25000e-01   7.11280e-01
>> ;
>> 1.82  0.1700
>>   CB       CB          0.00000  0.00000   A     3.39967e-01   3.59824e-01
>> ;
>> 1.91  0.0860
>>   N2       N2          0.00000  0.00000   A     3.25000e-01   7.11280e-01
>> ;
>> 1.82  0.1700
>>   NC       NC          0.00000  0.00000   A     3.25000e-01   7.11280e-01
>> ;
>> 1.82  0.1700
>>   CQ       CQ          0.00000  0.00000   A     3.39967e-01   3.59824e-01
>> ;
>> 1.91  0.0860
>>   ; IR3_GMX.top created by acpype (Rev: 403) on Wed Feb  4 11:55:46 2015
>> ; Include forcefield parameters
>> [ atomtypes ]
>>   ;name   bond_type     mass     charge   ptype   sigma
>> epsilon       Amb
>>   C        C           0.00000  0.00000   A     3.39967e-01   3.59824e-01
>> ;
>> 1.91  0.0860
>>   H        H           0.00000  0.00000   A     1.06908e-01   6.56888e-02
>> ;
>> 0.60 0.0157
>>   N        N           0.00000  0.00000   A     3.25000e-01   7.11280e-01
>> ;
>> 1.82  0.1700
>>
>> My first ligand gro file
>> GRoups of Organic Molecules in ACtion for Science
>>     73
>>      1NPD   OA22    1  -0.282 0.251 -5.719
>>      1NPD   OA23    2  -0.142   0.366  -5.542
>>      1NPD   OA24    3  -0.039 0.314 -5.771
>>      1NPD   P'A2    4  -0.145   0.285  -5.669
>>      1NPD     PA    5  -0.033  -0.056  -5.010
>>      1NPD     PN    6  -0.130  -0.245  -4.804
>>      1NPD    O3P    7  -0.126  -0.116  -4.893
>>      1NPD    N1A    8  -0.692 0.110 -5.840
>>      1NPD    N1N    9  -0.539  -0.355  -4.443
>>      1NPD    C2A   10  -0.613 0.000 -5.836
>> ...
>>      1NPD    H8A   73  -0.376 0.292 -5.440
>>     1.94588     0.88647     1.08377
>>
>> My second ligand gro file
>>
>> IR3_GMX.gro created by acpype (Rev: 403) on Wed Feb  4 11:55:46 2015
>> 22
>>      1IR3    CAA    1  10.182  10.576  10.387
>>      1IR3    HAB    2  10.211  10.640  10.305
>>      1IR3    HAA    3  10.075  10.577  10.396
>> ....
>>     1IR3    HAF   22  10.581  10.138  10.385
>>    20.72517  20.72517  20.72517
>>
>> but the system can`t go under energy minimization. This is my em.mdp
>>
>> title           = Minimization  ; Title of run
>> integrator      = steep         ; Algorithm (steep = steepest descent
>> minimization)
>> emtol           = 1000.0        ; Stop minimization when the maximum force
>> < 1000.0 kJ/mol
>> emstep          = 0.01      ; Energy step size
>> nsteps          = 500000                ; Maximum number of (minimization)
>> steps to perform
>> energygrps      = Protein NPD IR3       ; Which energy group(s) to write
>> to
>> disk
>> nstlist             = 1             ; Frequency to update the neighbor
>> list
>> and long range forces
>> cutoff-scheme       = Verlet
>> ns_type             = grid              ; Method to determine neighbor
>> list
>> (simple, grid)
>> rlist               = 1.0               ; Cut-off for making neighbor list
>> (short range forces)
>> coulombtype         = PME               ; Treatment of long range
>> electrostatic interactions
>> rcoulomb            = 1.0               ; long range electrostatic cut-off
>> rvdw                = 1.0               ; long range Van der Waals cut-off
>> pbc                     = xyz           ; Periodic Boundary Conditions
>>
>> I change emtol from 1000, then 500, then 100. No error generated but the
>> pdb output file goes wrong with the ligands. If I do the same procedure
>> with seperated ligand (only one [ atomtypes] in my_ligand_atomtypes.itp),
>> things goes well . Could you please help me where is the problem?
>> Many thanks in advance.
>>
>
> You'll have to be much more specific than "goes wrong with the ligands."
> What's happening?  Does EM fail or is the output just somehow screwed up?
> The ligand files are both set up within different boxes, so perhaps the
> construction of your system is incorrect somehow, but again, without
> specifics, I'm just guessing.
>
> -Justin
>
> --
> ==================================================
>
> Justin A. Lemkul, Ph.D.
> Ruth L. Kirschstein NRSA Postdoctoral Fellow
>
> Department of Pharmaceutical Sciences
> School of Pharmacy
> Health Sciences Facility II, Room 629
> University of Maryland, Baltimore
> 20 Penn St.
> Baltimore, MD 21201
>
> jalemkul at outerbanks.umaryland.edu | (410) 706-7441
> http://mackerell.umaryland.edu/~jalemkul
>
> ==================================================
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