Re: [gmx-users] pca-based MD

2012-12-15 Thread James Starlight
Hi, Thomas!

I'd like to ask you some addition questions about FMA. As I understood
from the FMA page that technique is something like integrator of
principal components (merge some PCs with identical functional motion
seen in the X-ray structures for instance) calculated from g_covar. So
FMA is also Hessia-based method (assuming that cov.matrix is inverse
of the Hessian) for studing functional motion in protein isnt?

Some technical questions:
Have you tried to extract functional modes from X-ray data set (not
from of unbiased md as in case of EDS) of your kinase for further
md-guiding ( e.g by means of EDS) of that protein along some
functional modes?
Have you tried use it with the gromacs 4.5 ? I've found that only for
older gromacs releases.
Does it possible to visualise motion along FM in vmd or mol script ?

Thanks for help

James

2012/9/23 Thomas Evangelidis :
> I presume you are referring to Essential Dynamics Sampling, described in
> section 3.14 of the manual (v4.5.4). There is also a great tool that finds
> the few PCs that are maximally correlated to a functional quantity (e.g.
> the volume of the active site). The technique is coined Functional Mode
> Analysis (FMA) and you can find more information at:
>
> http://xray.bmc.uu.se/~jochen/fma.html
>
> I have used FMA and worked pretty well in my case. I am wondering if anyone
> thought of using that technique to find the PCs that are maximally
> correlated to a functional quantity and then perform Essential Dynamics
> sampling  on these PCs to explore the conformational space that affects the
> most that functional quantity.
>
> I.e. I am studying a kinase in the wt and mutant form. Although the
> mutation is not near the active site there is a lot of discussion in the
> literature about the effect of the mutation on the opening of the catalytic
> cleft. Some people claim that one possible explanation of the over-activity
> of the mutant is the greater opening of the active site, which facilitates
> substrate binding and thus leads to enhanced reaction turn-over. In order
> to test this hypothesis with unbiased MD one would need tremendous computer
> resources and a lot of time (the kinase is gigantic). On the other hand one
> could run short simulations of the wt and mutant, do FMA to find the 10-20
> PCs that are maximally correlated to the volume of the active site, and
> then perform Essential Dynamics Sampling on these PCs to explore the
> conformational space that is highly correlated to the volume of the active
> site. After that, one could safely claim that the Hypothesis was true or
> false.
>
> I would be interested to read your comments on this.
>
> Thomas
>
>
> On 23 September 2012 11:19, James Starlight  wrote:
>
>> Dear Gromacs Users!
>>
>>
>> There are many publications about implementation of the pca-based MD
>> simulations for the investigation of the functional-relevant motions.
>> In that cases the eigenvectors are extracted from the relatively short
>> MD simulation of the investigated protein and than the biassed MD
>> simulation is started along chosen principal component which used as
>> the reaction coordinate.
>>
>> I'd like to know more about implementation of that technique in
>> Gromacs. E.g if I've performed some PCA and extracted eigenvectors how
>> I can run further simulation along one of the chosen PC ?
>>
>> Thanks for help
>> James
>> --
>> gmx-users mailing listgmx-users@gromacs.org
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>>
>
>
>
> --
>
> ==
>
> Thomas Evangelidis
>
> PhD student
> University of Athens
> Faculty of Pharmacy
> Department of Pharmaceutical Chemistry
> Panepistimioupoli-Zografou
> 157 71 Athens
> GREECE
>
> email: tev...@pharm.uoa.gr
>
>   teva...@gmail.com
>
>
> website: https://sites.google.com/site/thomasevangelidishomepage/
> --
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Re: [gmx-users] Energy minimization

2012-12-15 Thread Peter C. Lai
Probably remove the overlapping lipid then. Once you run MD it will repack.

On 2012-12-15 09:19:49PM -0800, Shima Arasteh wrote:
> Thanks for your kind reply.
> My system is composed of protein packed by lipids. The atoms overlapping, are 
> protein ( atom 288)  and lipid chain. I think if I move them, I may get some 
> other clashes, may I not? 
> Any other suggestion?
> 
> Thanks.
> 
> 
>  
> Sincerely,
> Shima
> 
> 
> - Original Message -
> From: Peter C. Lai 
> To: Shima Arasteh ; Discussion list for GROMACS 
> users 
> Cc: 
> Sent: Sunday, December 16, 2012 8:44 AM
> Subject: Re: [gmx-users] Energy minimization
> 
> It depends on what the atom is overlapping with and some conjecture as to 
> what might be causing the overlap:
> 
> You can always manually move it, either by editing the .gro file directly
> or using a tool like VMD to move it or the molecule/fragment it's attached to
> with the mouse and then display the new coordinates and the update the .gro 
> file.
> If it's something like a solvent molecule (water/lipid) and there is nowhere 
> to move the molecule, you can try deleting it too (just remmeber to update 
> .top file).
> 
> On 2012-12-15 08:58:59PM -0800, Shima Arasteh wrote:
> > When I find overlapping atom, what should I have to do? How is it possible 
> > to get solved?
> > 
> > 
> > Would you please help me? 
> > 
> > 
> > Sincerely,
> > Shima
> > 
> > 
> > 
> > From: Justin Lemkul 
> > To: Shima Arasteh ; Discussion list for 
> > GROMACS users  
> > Sent: Saturday, September 29, 2012 3:01 PM
> > Subject: Re: [gmx-users] Energy minimization
> > 
> > 
> > 
> > On 9/29/12 3:19 AM, Shima Arasteh wrote:
> > >
> > > Dear all,
> > >
> > > My system contains lipids, protein and water.
> > > I want to energy minimize it, so ran grompp:
> > >
> > >
> > > # grompp -f em.mdp -c system_solv_ions.gro -p topol.top -o em.tpr
> > >
> > > and then:
> > > # mdrun -v -deffnm em
> > >
> > >
> > > The output is:
> > > Steepest Descents:
> > >     Tolerance (Fmax)   =  1.0e+03
> > >     Number of steps    =        5
> > > Step=   14, Dmax= 1.2e-06 nm, Epot=  2.30004e+17 Fmax=         inf, atom= 
> > > 518
> > > Stepsize too small, or no change in energy.
> > > Converged to machine precision,
> > > but not to the requested precision Fmax < 1000
> > >
> > > Double precision normally gives you higher accuracy.
> > > You might need to increase your constraint accuracy, or turn
> > > off constraints alltogether (set constraints = none in mdp file)
> > >
> > > writing lowest energy coordinates.
> > >
> > > Back Off! I just backed up em.gro to ./#em.gro.3#
> > >
> > > Steepest Descents converged to machine precision in 15 steps,
> > > but did not reach the requested Fmax < 1000.
> > > Potential Energy  =  2.3000388e+17
> > > Maximum force     =            inf on atom 518
> > > Norm of force     =            inf
> > >
> > > It seems that atome 518 has an infinite energy. So I tried to apply the 
> > > suggestion of turning off the constraints in em.mdp. To do so, I added 
> > > "constraints=none" to mdp file, But it doesn't make different.
> > >
> > > Any suggestion please? I don't know how to solve this problem. Please 
> > > help me.
> > >
> > 
> > Atom 518 is overlapping with something nearby.  You will have to visualize 
> > the 
> > system to identify the source of the problem.
> > 
> > -Justin
> > 
> > -- 
> > 
> > 
> > Justin A. Lemkul, Ph.D.
> > Research Scientist
> > Department of Biochemistry
> > Virginia Tech
> > Blacksburg, VA
> > jalemkul[at]vt.edu | (540) 231-9080
> > http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin
> > 
> >  
> > -- 
> > gmx-users mailing list    gmx-users@gromacs.org
> > http://lists.gromacs.org/mailman/listinfo/gmx-users
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Re: [gmx-users] Re: Re: Is vacuum simulation NVT?

2012-12-15 Thread James Starlight
Dear Dr. Shirts!


Could you tell me is there any difference of different Tau_t ussage (
inverse friction in case of Stochastic dynamics) for simulation of
water-soluble as well as membrane-proteins ? In the first case I'm
using tau_t 2ps that is lower than internal water friction. In the
second case one part of protein could be in the membrane ( e.g
helixes) but other ( e.g loops) in water media. Both of that solvents
have different characteristic viscousity. So what Tau_t should be used
in stochastic dynamics for such biphastic systems?


James

2012/12/12 Jong Wha Lee :
> Thank you very much Justin, and thank you very much Michael. Your replies
> were of a great help.
>
>
>
>
>
> Jong Wha
>
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Re: [gmx-users] Essential dynamics (ED) sampling using make_edi

2012-12-15 Thread James Starlight
Dear collegues!

Oppositely to the Bipin Singh's question I wounder to know about the
exploring ( radius expansion) mode of EDS.  For example I define
essential
subspace from some collective coordinates and then run MD in that
subspace in exploring mode of EDS. Will the system be biased to the
some region of the collective space (like a guided-MD) or its only
some steered algorithm of reduction irrelevant degrees of freedom
(hight-frequency modes)? What parameters of EDS for time step as well
as scope should I use that my simulation be stereed-like not
biased-like ?

James

2012/12/12 Carsten Kutzner :
> Hi Bipin Singh,
>
> the parameters -deltaF0, -deltaF, -tau, -alpha, and -T are used only
> for flooding and have no effect in pure essential dynamics. Which coordinates
> appear in the output trajectory (*.trr, *.xtc) is exclusively controlled
> by .mdp options (i.e. the group you select there), not by the content of
> the .edi file.
>
> Best,
>   Carsten
>
>
> On Dec 11, 2012, at 6:27 PM, bipin singh  wrote:
>
>> Hello All,
>>
>> I want to use the essential dynamics (ED) sampling  method to simulate the
>> unfolding to folding process using make_edi option of GROMACS. For this
>> task I am using -radcon option (acceptance radius contraction along the
>> first two eigenvectors towards the folded structure (b4md.gro)) of make_edi
>> as below:
>>
>> *make_edi -f eigenvec.trr -eig eigenval.xvg -s topol.tpr -tar b4md.gro
>> -radcon 1-2 -o sam.edi
>> *
>> *b4md.gro:* folded structure (C-alpha only)
>> *topol.tpr: *all atom *
>> eigenvec.trr*:from g_covar (C-alpha only)
>>
>> Is this is the correct way of doing the ED sampling...
>>
>>
>> Also I am not sure about the following:
>>
>> *1)* How to judge the correct/appropriate value for the:
>>
>>  -maxedsteps
>>
>> *2)* How to judge the appropriate values for the following parameters for
>> an Essential dynamics sampling input *(or it is neglected for ED sampling
>> and used only for flooding input ) *
>>
>> -deltaF0
>> -deltaF
>> -tau
>> -alpha
>> -T
>>
>> *3) *Will the output trajectory (produced using mdrun -ei sam.edi ) contain
>> all atoms or only the C-alpha atoms (using the above make_edi command).
>>
>> --
>> *---
>> Thanks and Regards,
>> Bipin Singh*
>> --
>> gmx-users mailing listgmx-users@gromacs.org
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>
>
> --
> Dr. Carsten Kutzner
> Max Planck Institute for Biophysical Chemistry
> Theoretical and Computational Biophysics
> Am Fassberg 11, 37077 Goettingen, Germany
> Tel. +49-551-2012313, Fax: +49-551-2012302
> http://www.mpibpc.mpg.de/grubmueller/kutzner
> http://www.mpibpc.mpg.de/grubmueller/sppexa
>
> --
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Re: [gmx-users] Parametrisation of the cyclic nucleotides in Gromos force fields

2012-12-15 Thread James Starlight
Justin,

It's not quite understood for me why such errors occurs in the atoms
of standard residues when I've bounded them to the C term of my
chromophore if the geometry of the adjacent residues might not be
changed. So it likely that some errors occur during parametrization of
the molecule which I could not identify ( In any case I'll be very
thankful for anyone who can provideme with some other version of the
integrated chromophore in charm for my future effort-on-errors :)
The main problems which I've forced in the improper group definition (
I've not recognize in the paper of simulation in charmm22 what groups
should define as improper although Swiss param produce the big set of
such groups- see below )

In addition It'll be very hardly to connect chromophore with adjacent
residues mainly due to definition of the addition dihedrals.

Finally Im not quite sure about CMAP definition ( I've used
C NH1 CT1 C NH1 1 24 24\
C NH1 CT1 C N 1 24 24\
in the CMAP.itp with the atom names of chromophore

C NH1 CT1 C NC=O 1 24 24\
C NC=O CR C=O N=C 1 24 24\
C=C C=O NC=O CR C=O 1 24 24\
C=O NH1 CT1 C NH1 1 24 24\

where NC=O and N=C types correspond to  the N and CR is the C-alpha atoms


James


2012/12/15, Justin Lemkul :
>
>
> On 12/15/12 2:18 PM, James Starlight wrote:
>> So as I understood  it've happened because the conformation of the
>> adjacent residue is differ when that residue bounded to the
>> chromophore ( in comparison to the residue in unbound capped form).
>
> Conformation is irrelevant; atom types are all that matter here.
>
>> But in term of the backbone geometry of C and N-terms chromophore is
>> like a typical amino acid. Also Chromophore is defined as a protein in
>> the residue.dat.  When I've examined error log of my system I've
>> noticed that missing UB and dihedral parametrs of the i+1 residue have
>> never present in the ffbounded.itp ( the exact combination of the
>> triplet and quadruplet of atoms for UB and dihedral). Is there any
>> other ways to define termi of my non standard residue as the standard
>> one?
>>
>
> If a particular bonded interaction is not present in the parent force field,
> you
> have to derive it parameters for it.
>
> -Justin
>
> --
> 
>
> Justin A. Lemkul, Ph.D.
> Research Scientist
> Department of Biochemistry
> Virginia Tech
> Blacksburg, VA
> jalemkul[at]vt.edu | (540) 231-9080
> http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin
>
> 
> --
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Re: [gmx-users] Energy minimization

2012-12-15 Thread Shima Arasteh
Thanks for your kind reply.
My system is composed of protein packed by lipids. The atoms overlapping, are 
protein ( atom 288)  and lipid chain. I think if I move them, I may get some 
other clashes, may I not? 
Any other suggestion?

Thanks.


 
Sincerely,
Shima


- Original Message -
From: Peter C. Lai 
To: Shima Arasteh ; Discussion list for GROMACS 
users 
Cc: 
Sent: Sunday, December 16, 2012 8:44 AM
Subject: Re: [gmx-users] Energy minimization

It depends on what the atom is overlapping with and some conjecture as to 
what might be causing the overlap:

You can always manually move it, either by editing the .gro file directly
or using a tool like VMD to move it or the molecule/fragment it's attached to
with the mouse and then display the new coordinates and the update the .gro 
file.
If it's something like a solvent molecule (water/lipid) and there is nowhere 
to move the molecule, you can try deleting it too (just remmeber to update 
.top file).

On 2012-12-15 08:58:59PM -0800, Shima Arasteh wrote:
> When I find overlapping atom, what should I have to do? How is it possible to 
> get solved?
> 
> 
> Would you please help me? 
> 
> 
> Sincerely,
> Shima
> 
> 
> 
> From: Justin Lemkul 
> To: Shima Arasteh ; Discussion list for GROMACS 
> users  
> Sent: Saturday, September 29, 2012 3:01 PM
> Subject: Re: [gmx-users] Energy minimization
> 
> 
> 
> On 9/29/12 3:19 AM, Shima Arasteh wrote:
> >
> > Dear all,
> >
> > My system contains lipids, protein and water.
> > I want to energy minimize it, so ran grompp:
> >
> >
> > # grompp -f em.mdp -c system_solv_ions.gro -p topol.top -o em.tpr
> >
> > and then:
> > # mdrun -v -deffnm em
> >
> >
> > The output is:
> > Steepest Descents:
> >     Tolerance (Fmax)   =  1.0e+03
> >     Number of steps    =        5
> > Step=   14, Dmax= 1.2e-06 nm, Epot=  2.30004e+17 Fmax=         inf, atom= 
> > 518
> > Stepsize too small, or no change in energy.
> > Converged to machine precision,
> > but not to the requested precision Fmax < 1000
> >
> > Double precision normally gives you higher accuracy.
> > You might need to increase your constraint accuracy, or turn
> > off constraints alltogether (set constraints = none in mdp file)
> >
> > writing lowest energy coordinates.
> >
> > Back Off! I just backed up em.gro to ./#em.gro.3#
> >
> > Steepest Descents converged to machine precision in 15 steps,
> > but did not reach the requested Fmax < 1000.
> > Potential Energy  =  2.3000388e+17
> > Maximum force     =            inf on atom 518
> > Norm of force     =            inf
> >
> > It seems that atome 518 has an infinite energy. So I tried to apply the 
> > suggestion of turning off the constraints in em.mdp. To do so, I added 
> > "constraints=none" to mdp file, But it doesn't make different.
> >
> > Any suggestion please? I don't know how to solve this problem. Please help 
> > me.
> >
> 
> Atom 518 is overlapping with something nearby.  You will have to visualize 
> the 
> system to identify the source of the problem.
> 
> -Justin
> 
> -- 
> 
> 
> Justin A. Lemkul, Ph.D.
> Research Scientist
> Department of Biochemistry
> Virginia Tech
> Blacksburg, VA
> jalemkul[at]vt.edu | (540) 231-9080
> http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin
> 
>  
> -- 
> gmx-users mailing list    gmx-users@gromacs.org
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> * Please search the archive at 
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Re: [gmx-users] Energy minimization

2012-12-15 Thread Peter C. Lai
It depends on what the atom is overlapping with and some conjecture as to 
what might be causing the overlap:

You can always manually move it, either by editing the .gro file directly
or using a tool like VMD to move it or the molecule/fragment it's attached to
with the mouse and then display the new coordinates and the update the .gro 
file.
If it's something like a solvent molecule (water/lipid) and there is nowhere 
to move the molecule, you can try deleting it too (just remmeber to update 
.top file).

On 2012-12-15 08:58:59PM -0800, Shima Arasteh wrote:
> When I find overlapping atom, what should I have to do? How is it possible to 
> get solved?
> 
> 
> Would you please help me? 
> 
> 
> Sincerely,
> Shima
> 
> 
> 
> From: Justin Lemkul 
> To: Shima Arasteh ; Discussion list for GROMACS 
> users  
> Sent: Saturday, September 29, 2012 3:01 PM
> Subject: Re: [gmx-users] Energy minimization
> 
> 
> 
> On 9/29/12 3:19 AM, Shima Arasteh wrote:
> >
> > Dear all,
> >
> > My system contains lipids, protein and water.
> > I want to energy minimize it, so ran grompp:
> >
> >
> > # grompp -f em.mdp -c system_solv_ions.gro -p topol.top -o em.tpr
> >
> > and then:
> > # mdrun -v -deffnm em
> >
> >
> > The output is:
> > Steepest Descents:
> >     Tolerance (Fmax)   =  1.0e+03
> >     Number of steps    =        5
> > Step=   14, Dmax= 1.2e-06 nm, Epot=  2.30004e+17 Fmax=         inf, atom= 
> > 518
> > Stepsize too small, or no change in energy.
> > Converged to machine precision,
> > but not to the requested precision Fmax < 1000
> >
> > Double precision normally gives you higher accuracy.
> > You might need to increase your constraint accuracy, or turn
> > off constraints alltogether (set constraints = none in mdp file)
> >
> > writing lowest energy coordinates.
> >
> > Back Off! I just backed up em.gro to ./#em.gro.3#
> >
> > Steepest Descents converged to machine precision in 15 steps,
> > but did not reach the requested Fmax < 1000.
> > Potential Energy  =  2.3000388e+17
> > Maximum force     =            inf on atom 518
> > Norm of force     =            inf
> >
> > It seems that atome 518 has an infinite energy. So I tried to apply the 
> > suggestion of turning off the constraints in em.mdp. To do so, I added 
> > "constraints=none" to mdp file, But it doesn't make different.
> >
> > Any suggestion please? I don't know how to solve this problem. Please help 
> > me.
> >
> 
> Atom 518 is overlapping with something nearby.  You will have to visualize 
> the 
> system to identify the source of the problem.
> 
> -Justin
> 
> -- 
> 
> 
> Justin A. Lemkul, Ph.D.
> Research Scientist
> Department of Biochemistry
> Virginia Tech
> Blacksburg, VA
> jalemkul[at]vt.edu | (540) 231-9080
> http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin
> 
>  
> -- 
> gmx-users mailing listgmx-users@gromacs.org
> http://lists.gromacs.org/mailman/listinfo/gmx-users
> * Please search the archive at 
> http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
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Re: [gmx-users] Energy minimization

2012-12-15 Thread Shima Arasteh
When I find overlapping atom, what should I have to do? How is it possible to 
get solved?


Would you please help me? 


Sincerely,
Shima



From: Justin Lemkul 
To: Shima Arasteh ; Discussion list for GROMACS 
users  
Sent: Saturday, September 29, 2012 3:01 PM
Subject: Re: [gmx-users] Energy minimization



On 9/29/12 3:19 AM, Shima Arasteh wrote:
>
> Dear all,
>
> My system contains lipids, protein and water.
> I want to energy minimize it, so ran grompp:
>
>
> # grompp -f em.mdp -c system_solv_ions.gro -p topol.top -o em.tpr
>
> and then:
> # mdrun -v -deffnm em
>
>
> The output is:
> Steepest Descents:
>     Tolerance (Fmax)   =  1.0e+03
>     Number of steps    =        5
> Step=   14, Dmax= 1.2e-06 nm, Epot=  2.30004e+17 Fmax=         inf, atom= 518
> Stepsize too small, or no change in energy.
> Converged to machine precision,
> but not to the requested precision Fmax < 1000
>
> Double precision normally gives you higher accuracy.
> You might need to increase your constraint accuracy, or turn
> off constraints alltogether (set constraints = none in mdp file)
>
> writing lowest energy coordinates.
>
> Back Off! I just backed up em.gro to ./#em.gro.3#
>
> Steepest Descents converged to machine precision in 15 steps,
> but did not reach the requested Fmax < 1000.
> Potential Energy  =  2.3000388e+17
> Maximum force     =            inf on atom 518
> Norm of force     =            inf
>
> It seems that atome 518 has an infinite energy. So I tried to apply the 
> suggestion of turning off the constraints in em.mdp. To do so, I added 
> "constraints=none" to mdp file, But it doesn't make different.
>
> Any suggestion please? I don't know how to solve this problem. Please help me.
>

Atom 518 is overlapping with something nearby.  You will have to visualize the 
system to identify the source of the problem.

-Justin

-- 


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

 
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Re: [gmx-users] gold-S simulation

2012-12-15 Thread francesco oteri
Hi fatemeh,
I am looking for prameters like yours, where have you took the parameters
for gold and gold-aminoacid inteaction?

Francesco


2012/12/16 Peter C. Lai 

> Where is the .itp file for the system?
>
> On 2012-12-15 01:40:27PM -0800, fatemeh ramezani wrote:
> > hi
> >
> >
> > I'm simulating gold atom interaction with  aminoacidcys. I have made
> gold-cys.pdb by hyperchem software:
> >
> > HETATM1  N   CYS 1   0.000   1.335   0.000
> > HETATM2  CA  CYS 1  -0.683   1.818  -1.183
> > HETATM3  C   CYS 1  -0.705   3.339  -1.221
> > HETATM4  O   CYS 1  -0.184   3.993  -0.319
> > HETATM5  CB  CYS 1  -2.127   1.330  -1.221
> > HETATM6  SG  CYS 1  -3.106   1.859  -2.649
> > HETATM8 AU   AU  8  -2.833   0.428  -1.793
> > HETATM9 AU   AU  9  -2.647   0.381  -2.869
> > HETATM   10 AU   AU 10  -1.691   1.360  -3.093
> > HETATM   11 AU   AU 11  -0.647   2.706  -2.135
> > HETATM   12 AU   AU 12  -2.742   0.834  -0.456
> > HETATM   13 AU   AU 13  -1.691   2.061  -0.043
> > HETATM   14 AU   AU 14  -0.783   3.136   0.376
> > HETATM   15 AU   AU 15   0.095   3.750  -1.068
> > HETATM   16 AU   AU 16  -2.929   2.480  -2.204
> > HETATM   17 AU   AU 17  -3.285   1.594  -3.328
> > HETATM   18 AU   AU 18  -2.544   2.593  -3.763
> > HETATM   19 AU   AU 19  -1.951   1.260  -2.303
> > CONECT12
> > CONECT01
> > CONECT2135
> > CONECT02
> > CONECT324
> > CONECT43
> > CONECT526
> > CONECT05
> > CONECT05
> > CONECT65
> > CONECT06
> > CONECT06
> > CONECT06
> > END
> >
> >
> >
> > I started simulation by this pdb file. I'm using OPLSAA force field and
> also I added gold parameter in ffnonbonded.itp  :
> > .
> > .
> > .
> > ; Added by DvdS 05/2005 copied from GROMACS force field.
> >  SI SI 1428.08000 0.000A3.38550e-01
> 2.44704e+00
> >  AU AU 79   196.9700 0.000   A0.29510e+00
> 22.1120e+00
> >
> > [ nonbond_params ]
> > AU  AU   10.0e+00
> 0.0e+00
> >
> >
> > ; SC 08/2007: Special Au-N vdw to simulate chemical bond between
> gold-imidazole
> >  AU opls_511 13.07000e-01
> 3.96000e+00
> >
> > ; SC 05/2008: special Au-C and Au-H to simulate pi-systems
> alkenes+benzene (and PHE)
> >  AU opls_142 13.21000e-1
> 2.65400e+00
> >  AU opls_143 13.21000e-1
> 2.65400e+00
> >  AU opls_144 12.67000e-1
> 1.66500e+00
> >  AU opls_145 13.2e-1
> 2.54600e+00
> >  AU opls_146 12.67000e-1
> 1.66500e+00
> >  AU opls_150 13.21000e-1
> 2.65400e+00
> >
> > ; +imidazole and His
> >  AU opls_506 13.21000e-1
> 2.54000e+00
> >  AU opls_507 13.21000e-1
> 2.54000e+00
> >  AU opls_508 13.21000e-1
> 2.54000e+00
> >
> > ; +HisH
> >  AU opls_509 13.21000e-1
> 2.54000e+00
> >  AU opls_510 13.21000e-1
> 2.54000e+00
> > ; +TYR
> >  AU opls_166 13.21000e-1
> 2.54000e+00
> > ; +TRP
> >  AU opls_500 13.21000e-1
> 2.54000e+00
> >  AU opls_514 13.21000e-1
> 2.54000e+00
> >  AU opls_501 13.21000e-1
> 2.54000e+00
> >  AU opls_502 13.55000e-1
> 3.55000e+00
> >
> > and I concidered AU-S as bonding connection and I added its parameter
> (bond stretch, dihedral and angle ) in ffbonded.itp file:
> > [ bondtypes ]
> > ; ij  func   b0  kb
> > .
> > .
> > .
> > AUSH  10.24000   165528.0   ;
> > AUS   10.24000   165528.0   ;
> > AUSG  10.24000   165528.0   ;
> > .
> > .
> > .
> > [ angletypes ]
> > ;  ijk  func   th0   cth
> > .
> > .
> > .
> >   AU SG CB  1   109.00 46.34
> >   AU SH CB  1   109.00 46.34
> >   AU S  CB  1   109.00 46.34
> > .
> > .
> > .
> > [ dihedraltypes ]
> > .
> > .
> > .
> > #define improper_AU_S_CB_CA-180.0  1.2958 2
> >
> > #define improper_AU_SH_CB_CA   -180.0  1.2958 2
> >
> > #define improper_AU_SG_CB_CA-180   1.2958 2
> >
> > #define improper_AU_S_C_C 19   0.9196 2
> >
> > #define improper_AU_SH_C_C19   0.9196 2
> >
> > #define improper_AU_SG_C_C19   0.9196 2
> > .
> > .
> > .
> >
> > when I ru

Re: [gmx-users] gold-S simulation

2012-12-15 Thread Peter C. Lai
Where is the .itp file for the system?

On 2012-12-15 01:40:27PM -0800, fatemeh ramezani wrote:
> hi 
> 
> 
> I'm simulating gold atom interaction with  aminoacidcys. I have made 
> gold-cys.pdb by hyperchem software:
> 
> HETATM    1  N   CYS 1   0.000   1.335   0.000
> HETATM    2  CA  CYS 1  -0.683   1.818  -1.183
> HETATM    3  C   CYS 1  -0.705   3.339  -1.221
> HETATM    4  O   CYS 1  -0.184   3.993  -0.319
> HETATM    5  CB  CYS 1  -2.127   1.330  -1.221
> HETATM    6  SG  CYS 1  -3.106   1.859  -2.649
> HETATM    8 AU   AU  8  -2.833   0.428  -1.793
> HETATM    9 AU   AU  9  -2.647   0.381  -2.869
> HETATM   10 AU   AU 10  -1.691   1.360  -3.093
> HETATM   11 AU   AU 11  -0.647   2.706  -2.135
> HETATM   12 AU   AU 12  -2.742   0.834  -0.456
> HETATM   13 AU   AU 13  -1.691   2.061  -0.043
> HETATM   14 AU   AU 14  -0.783   3.136   0.376
> HETATM   15 AU   AU 15   0.095   3.750  -1.068
> HETATM   16 AU   AU 16  -2.929   2.480  -2.204
> HETATM   17 AU   AU 17  -3.285   1.594  -3.328
> HETATM   18 AU   AU 18  -2.544   2.593  -3.763
> HETATM   19 AU   AU 19  -1.951   1.260  -2.303
> CONECT    1    2
> CONECT    0    1
> CONECT    2    1    3    5
> CONECT    0    2
> CONECT    3    2    4
> CONECT    4    3
> CONECT    5    2    6
> CONECT    0    5
> CONECT    0    5
> CONECT    6    5
> CONECT    0    6
> CONECT    0    6
> CONECT    0    6
> END
> 
>  
> 
> I started simulation by this pdb file. I'm using OPLSAA force field and also 
> I added gold parameter in ffnonbonded.itp  :
> .
> .
> .
> ; Added by DvdS 05/2005 copied from GROMACS force field.   
>  SI SI 14    28.08000 0.000    A    3.38550e-01  
> 2.44704e+00
>  AU AU 79   196.9700 0.000   A    0.29510e+00  22.1120e+00
> 
> [ nonbond_params ]
> AU  AU   1    0.0e+00  0.0e+00
> 
> 
> ; SC 08/2007: Special Au-N vdw to simulate chemical bond between 
> gold-imidazole
>  AU opls_511 1    3.07000e-01  3.96000e+00
>  
> ; SC 05/2008: special Au-C and Au-H to simulate pi-systems alkenes+benzene 
> (and PHE)
>  AU opls_142 1    3.21000e-1   2.65400e+00
>  AU opls_143 1    3.21000e-1   2.65400e+00
>  AU opls_144 1    2.67000e-1   1.66500e+00
>  AU opls_145 1    3.2e-1   2.54600e+00
>  AU opls_146 1    2.67000e-1   1.66500e+00
>  AU opls_150 1    3.21000e-1   2.65400e+00
>  
> ; +imidazole and His
>  AU opls_506 1    3.21000e-1   2.54000e+00
>  AU opls_507 1    3.21000e-1   2.54000e+00
>  AU opls_508 1    3.21000e-1   2.54000e+00
> 
> ; +HisH
>  AU opls_509 1    3.21000e-1   2.54000e+00
>  AU opls_510 1    3.21000e-1   2.54000e+00
> ; +TYR
>  AU opls_166 1    3.21000e-1   2.54000e+00
> ; +TRP
>  AU opls_500 1    3.21000e-1   2.54000e+00
>  AU opls_514 1    3.21000e-1   2.54000e+00
>  AU opls_501 1    3.21000e-1   2.54000e+00
>  AU opls_502 1    3.55000e-1   3.55000e+00
> 
> and I concidered AU-S as bonding connection and I added its parameter (bond 
> stretch, dihedral and angle ) in ffbonded.itp file: 
> [ bondtypes ]
> ; i    j  func   b0  kb
> .
> .
> .
> AU    SH  1    0.24000   165528.0   ;
> AU    S   1    0.24000   165528.0   ;
> AU    SG  1    0.24000   165528.0   ;
> .
> .
> .
> [ angletypes ]
> ;  i    j    k  func   th0   cth
> .
> .
> .
>   AU SG CB  1   109.00 46.34
>   AU SH CB  1   109.00 46.34
>   AU S  CB  1   109.00 46.34
> .
> .
> .
> [ dihedraltypes ]
> .
> .
> .
> #define improper_AU_S_CB_CA    -180.0  1.2958 2 
> 
> #define improper_AU_SH_CB_CA   -180.0  1.2958 2
> 
> #define improper_AU_SG_CB_CA    -180   1.2958 2
> 
> #define improper_AU_S_C_C 19   0.9196 2
> 
> #define improper_AU_SH_C_C    19   0.9196 2
> 
> #define improper_AU_SG_C_C    19   0.9196 2
> .
> .
> .
> 
> when I run my simulation I dont see any interaction or affinity between gold 
> atom and S atom of cystein, while it is clear that gold shoud has interaction 
> with sulfur. what is its reason? I'm completely confused. I tried anythings 
> that I can but my system doesn't work.
> 
> please help me
>  
> 
> Fatemeh Ramezani
> -- 
> gmx-users mailing listgmx-users@gromacs.org
> http

[gmx-users] gold-S simulation

2012-12-15 Thread fatemeh ramezani
hi 


I'm simulating gold atom interaction with  aminoacidcys. I have made 
gold-cys.pdb by hyperchem software:

HETATM    1  N   CYS 1   0.000   1.335   0.000
HETATM    2  CA  CYS 1  -0.683   1.818  -1.183
HETATM    3  C   CYS 1  -0.705   3.339  -1.221
HETATM    4  O   CYS 1  -0.184   3.993  -0.319
HETATM    5  CB  CYS 1  -2.127   1.330  -1.221
HETATM    6  SG  CYS 1  -3.106   1.859  -2.649
HETATM    8 AU   AU  8  -2.833   0.428  -1.793
HETATM    9 AU   AU  9  -2.647   0.381  -2.869
HETATM   10 AU   AU 10  -1.691   1.360  -3.093
HETATM   11 AU   AU 11  -0.647   2.706  -2.135
HETATM   12 AU   AU 12  -2.742   0.834  -0.456
HETATM   13 AU   AU 13  -1.691   2.061  -0.043
HETATM   14 AU   AU 14  -0.783   3.136   0.376
HETATM   15 AU   AU 15   0.095   3.750  -1.068
HETATM   16 AU   AU 16  -2.929   2.480  -2.204
HETATM   17 AU   AU 17  -3.285   1.594  -3.328
HETATM   18 AU   AU 18  -2.544   2.593  -3.763
HETATM   19 AU   AU 19  -1.951   1.260  -2.303
CONECT    1    2
CONECT    0    1
CONECT    2    1    3    5
CONECT    0    2
CONECT    3    2    4
CONECT    4    3
CONECT    5    2    6
CONECT    0    5
CONECT    0    5
CONECT    6    5
CONECT    0    6
CONECT    0    6
CONECT    0    6
END

 

I started simulation by this pdb file. I'm using OPLSAA force field and also I 
added gold parameter in ffnonbonded.itp  :
.
.
.
; Added by DvdS 05/2005 copied from GROMACS force field.   
 SI SI 14    28.08000 0.000    A    3.38550e-01  2.44704e+00
 AU AU 79   196.9700 0.000   A    0.29510e+00  22.1120e+00

[ nonbond_params ]
AU  AU   1    0.0e+00  0.0e+00


; SC 08/2007: Special Au-N vdw to simulate chemical bond between gold-imidazole
 AU opls_511 1    3.07000e-01  3.96000e+00
 
; SC 05/2008: special Au-C and Au-H to simulate pi-systems alkenes+benzene (and 
PHE)
 AU opls_142 1    3.21000e-1   2.65400e+00
 AU opls_143 1    3.21000e-1   2.65400e+00
 AU opls_144 1    2.67000e-1   1.66500e+00
 AU opls_145 1    3.2e-1   2.54600e+00
 AU opls_146 1    2.67000e-1   1.66500e+00
 AU opls_150 1    3.21000e-1   2.65400e+00
 
; +imidazole and His
 AU opls_506 1    3.21000e-1   2.54000e+00
 AU opls_507 1    3.21000e-1   2.54000e+00
 AU opls_508 1    3.21000e-1   2.54000e+00

; +HisH
 AU opls_509 1    3.21000e-1   2.54000e+00
 AU opls_510 1    3.21000e-1   2.54000e+00
; +TYR
 AU opls_166 1    3.21000e-1   2.54000e+00
; +TRP
 AU opls_500 1    3.21000e-1   2.54000e+00
 AU opls_514 1    3.21000e-1   2.54000e+00
 AU opls_501 1    3.21000e-1   2.54000e+00
 AU opls_502 1    3.55000e-1   3.55000e+00

and I concidered AU-S as bonding connection and I added its parameter (bond 
stretch, dihedral and angle ) in ffbonded.itp file: 
[ bondtypes ]
; i    j  func   b0  kb
.
.
.
AU    SH  1    0.24000   165528.0   ;
AU    S   1    0.24000   165528.0   ;
AU    SG  1    0.24000   165528.0   ;
.
.
.
[ angletypes ]
;  i    j    k  func   th0   cth
.
.
.
  AU SG CB  1   109.00 46.34
  AU SH CB  1   109.00 46.34
  AU S  CB  1   109.00 46.34
.
.
.
[ dihedraltypes ]
.
.
.
#define improper_AU_S_CB_CA    -180.0  1.2958 2 

#define improper_AU_SH_CB_CA   -180.0  1.2958 2

#define improper_AU_SG_CB_CA    -180   1.2958 2

#define improper_AU_S_C_C 19   0.9196 2

#define improper_AU_SH_C_C    19   0.9196 2

#define improper_AU_SG_C_C    19   0.9196 2
.
.
.

when I run my simulation I dont see any interaction or affinity between gold 
atom and S atom of cystein, while it is clear that gold shoud has interaction 
with sulfur. what is its reason? I'm completely confused. I tried anythings 
that I can but my system doesn't work.

please help me
 

Fatemeh Ramezani
--
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http://lists.gromacs.org/mailman/listinfo/gmx-users
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Re: [gmx-users] Parametrisation of the cyclic nucleotides in Gromos force fields

2012-12-15 Thread Justin Lemkul



On 12/15/12 2:18 PM, James Starlight wrote:

So as I understood  it've happened because the conformation of the
adjacent residue is differ when that residue bounded to the
chromophore ( in comparison to the residue in unbound capped form).


Conformation is irrelevant; atom types are all that matter here.


But in term of the backbone geometry of C and N-terms chromophore is
like a typical amino acid. Also Chromophore is defined as a protein in
the residue.dat.  When I've examined error log of my system I've
noticed that missing UB and dihedral parametrs of the i+1 residue have
never present in the ffbounded.itp ( the exact combination of the
triplet and quadruplet of atoms for UB and dihedral). Is there any
other ways to define termi of my non standard residue as the standard
one?



If a particular bonded interaction is not present in the parent force field, you 
have to derive it parameters for it.


-Justin

--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] Parametrisation of the cyclic nucleotides in Gromos force fields

2012-12-15 Thread James Starlight
So as I understood  it've happened because the conformation of the
adjacent residue is differ when that residue bounded to the
chromophore ( in comparison to the residue in unbound capped form).
But in term of the backbone geometry of C and N-terms chromophore is
like a typical amino acid. Also Chromophore is defined as a protein in
the residue.dat.  When I've examined error log of my system I've
noticed that missing UB and dihedral parametrs of the i+1 residue have
never present in the ffbounded.itp ( the exact combination of the
triplet and quadruplet of atoms for UB and dihedral). Is there any
other ways to define termi of my non standard residue as the standard
one?

James

2012/12/15, Justin Lemkul :
>
>
> On 12/15/12 1:34 PM, James Starlight wrote:
>> The last problem with which I've forced during preparation of my
>> chromophore is when I've defined bond between chromophore and the next
>> residue
>>
>>
>> C+N
>>
>> That produce 15 addition errors about unknown UB and dihedral types
>> in the atoms of the next residue (not in the chromophore) where all UB
>> and impropers must be defined initially.
>> Why that occurs ?
>>
>
> Because the combinations of parameters don't exist in ffbonded.itp.
>
> -Justin
>
>> 2012/12/14, James Starlight :
>>> The topology with the below params produced that 118 errors during
>>> grompp processings ( after pdb2gmx processing the geoetry of the
>>> mollecule was correct )
>>>
>>> [CRN]
>>>   [ atoms ]
>>> CG2  CA-0.0900 0
>>> CD1  CA-0.0800 1
>>> CD2  CA-0.0800 2
>>> CE1  CA-0.2800 3
>>> CE2  CA-0.2800 4
>>> CZ   CA 0.4500 5
>>> NNH1   -0.4700 6
>>> CA1  CPH1   0.1000 7
>>> CB1  CT1   -0.1400 8
>>> CG1  CT30.0900 9
>>> OG1  OH1   -0.6600 10 ;!-0.6800
>>> C1   CPH2   0.5000 11
>>> N2   NR2   -0.6000 12
>>> N3   NR1   -0.5700 13
>>> C2   CPH1   0.5700 14
>>> O3   O -0.5700 15
>>> CA2  CPH1   0.1000 16
>>> CA3  CPH10.1000 17
>>> CC  0.5100 18
>>> OO -0.5100 19
>>> CB2  CE1   -0.1400 20
>>> OH   O -0.6200 21
>>> HA1  HB 0.0700 22
>>> HA32 HB 0.0700 23
>>> HA33 HB 0.0700 24
>>> HD1  HP 0.1400 25
>>> HD2  HP 0.1400 26
>>> HE1  HP 0.1000 27
>>> HE2  HP 0.1000 28
>>> HG11 HA 0.0900 29
>>> HG12 HA 0.0900 30
>>> HG13 HA 0.0900 31
>>> HOG1 H  0.4300 32
>>> HB2  HA10.2100 33
>>> H11  H  0.3700 34
>>> HB1  HA10.2100 36
>>>   [ bonds ]
>>> HG11 CG1
>>> HG12 CG1
>>> CG1  HG13
>>> CG1  CB1
>>> OG1  HOG1
>>> OG1  CB1
>>> CB1  HB1
>>> CB1  CA1
>>> HE2  CE2
>>> NH11
>>> NCA1
>>> CA1  HA1
>>> CA1  C1
>>> CE2  CD2
>>> CE2  CZ
>>> HD2  CD2
>>> OH   CZ
>>> CD2  CG2
>>> CZ   CE1
>>> N2   C1
>>> N2   CA2
>>> C1   N3
>>> HA33 CA3
>>> CG2  CB2
>>> CG2  CD1
>>> CE1  HE1
>>> CE1  CD1
>>> CA2  CB2
>>> CA2  C2
>>> N3   CA3
>>> N3   C2
>>> CB2  HB2
>>> CA3  C
>>> CA3  HA32
>>> CD1  HD1
>>> C2   O3
>>> CO
>>>
>>>   [ impropers ]
>>> CG2  CD1  CB2  CD2
>>> CD1  CE1  CG2  HD1
>>> CD2  CE2  CG2  HD2
>>> CE2  CZ   CD2  HE2
>>> CB2  CA2  CG2  HB2
>>> CA2  N2   CB2  C2
>>> C1   CA1  N2   N3
>>> CA1  NC1   CB1
>>> CA1  CB1  C1   HA1
>>> CB1  OG1  CA1  CG1
>>> CB1  CG1  CA1  HB1
>>> C2   N3   CA2  O3
>>> N3   C2   C1   CA3
>>> CA3  CN3   HA33
>>> CA3  HA33 N3   HA32
>>> CZ   CE1  CE2  OH
>>> CE1  CZ   CD1  HE1
>>> CG1  HG11 CB1  HG12
>>> CG1  HG11 CB1  HG13
>>> ; with next residue
>>> C+N   CA3  O
>>> ; with previous residue
>>> N-C   CA1  H11
>>> [ cmap ]
>>> -C  N  CA1  C1  N2
>>> CA2 C2 N3 CA3 C
>>>
>>> The only in that I not sure in that model is the corrections in the
>>> cmap.itp which I added (I've used first two terms which are correspond
>>> to the backbone atoms of the standart amino acid:
>>> C NH1 CT1 C NH1 1 24 24\
>>> C NH1 CT1 C N 1 24 24\
>>>   and renamed it to the chromophore atom names)
>>>
>>> by the way If you had had your rtp of the chromophore which you've
>>> done in accordance to that paper could you provide me with them for
>>> comparison with my model ?
>>>
>>>
>>> James
>>>
>>> 2012/12/14, Justin Lemkul :


 On 12/14/12 3:20 PM, James Starlight wrote:
> Justin,
>
> in the case of the system with the atom types assigned from that paper
> the grompp produced above 118 errors of non standard bond, angle as
> well as dihedral types ;o So it' seems that some 118 addition terms
> must be added to the ffbonded.itp to the existing charmm parameters(
> it's uncommon for me because in that case the atom names werefrom
> standart charmm ff but the total number of errors was bigger than in
> case of Swiss params non-standart names usage).
>

 I'm not sure why there were so many errors when you used those
 parameters.
 Like
 I said, we've used them before.  I recall a few errors along the way,
 but
 manual
 assignment of the bonded parameters according to the paper is fairly
 straightforward.

> By the way I've simulated choromophore produced by SWISS ( 

Re: [gmx-users] different distance calculated by grompp and g_dist when doing umbrella sampling simulations

2012-12-15 Thread Justin Lemkul



On 12/15/12 4:03 AM, mirc...@sjtu.edu.cn wrote:

Dear All:

I encountered a problem when doing umbrella sampling. The distance calculated 
by grompp and g_dist is different, as shown by the following:

grompp  z component of g_dist(since I am constraining the distance between two 
groups along the z direction, I should calculate the z component of the 
distance, right?)
2.986   2.96
2.953   2.95
2.931   2.92
2.936   2.9355
2.844   2.83

There is an obvious difference between the distance calculated by the grompp 
and the g_dist, I also found that some post similar problems in the maillist, 
but I didn't found answers for the following questions.
(1)Why there is a such difference?


Probably because the default pull_pbcatom1 doesn't represent your pulled group 
very well.  By default, the atom is chosen as the numerical middle, which may 
not correspond to the geometric middle in a complex molecule.



(2)Also, does anyone know which value is used in the umbrella sampling 
simulations, the grompp result or the g_dist result?


Whatever grompp tells you is what is used.


(3)how to choose the right starting conformations since there is such a 
difference?



More likely, you should start by defining pull_pbcatom1 more appropriately.

-Justin


I also pasted the pull code I used as follows:

pull=   umbrella
pull_geometry   =   direction
pull_dim=   N N Y
pull_start  =   yes
pull_nstxout=   500
pull_nstfout=   500
pull_ngroups= 1
pull_group0 =   Protein
pull_group1 =   AMA
pull_init1  =   0
pull_rate1  =   0.000;nm/ps
pull_k1 =   4500 ;kJ/mol/nm^2


Thanks in advance!!

Best regards,
Ruo-Xu Gu



--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] Printing thermo data

2012-12-15 Thread Justin Lemkul



On 12/15/12 10:58 AM, John Doe wrote:


Hello All,

I was wondering if it's possible to print to a file different thermo data, such 
as force on atoms, pressure, bond energies, ect?



Energy terms are stored in the .edr file and forces on atoms are stored in the 
.trr file provided you set nstfout > 0 in the .mdp file.


-Justin

--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] Parametrisation of the cyclic nucleotides in Gromos force fields

2012-12-15 Thread Justin Lemkul



On 12/15/12 1:34 PM, James Starlight wrote:

The last problem with which I've forced during preparation of my
chromophore is when I've defined bond between chromophore and the next
residue


C+N

That produce 15 addition errors about unknown UB and dihedral types
in the atoms of the next residue (not in the chromophore) where all UB
and impropers must be defined initially.
Why that occurs ?



Because the combinations of parameters don't exist in ffbonded.itp.

-Justin


2012/12/14, James Starlight :

The topology with the below params produced that 118 errors during
grompp processings ( after pdb2gmx processing the geoetry of the
mollecule was correct )

[CRN]
  [ atoms ]
CG2  CA-0.0900 0
CD1  CA-0.0800 1
CD2  CA-0.0800 2
CE1  CA-0.2800 3
CE2  CA-0.2800 4
CZ   CA 0.4500 5
NNH1   -0.4700 6
CA1  CPH1   0.1000 7
CB1  CT1   -0.1400 8
CG1  CT30.0900 9
OG1  OH1   -0.6600 10 ;!-0.6800
C1   CPH2   0.5000 11
N2   NR2   -0.6000 12
N3   NR1   -0.5700 13
C2   CPH1   0.5700 14
O3   O -0.5700 15
CA2  CPH1   0.1000 16
CA3  CPH10.1000 17
CC  0.5100 18
OO -0.5100 19
CB2  CE1   -0.1400 20
OH   O -0.6200 21
HA1  HB 0.0700 22
HA32 HB 0.0700 23
HA33 HB 0.0700 24
HD1  HP 0.1400 25
HD2  HP 0.1400 26
HE1  HP 0.1000 27
HE2  HP 0.1000 28
HG11 HA 0.0900 29
HG12 HA 0.0900 30
HG13 HA 0.0900 31
HOG1 H  0.4300 32
HB2  HA10.2100 33
H11  H  0.3700 34
HB1  HA10.2100 36
  [ bonds ]
HG11 CG1
HG12 CG1
CG1  HG13
CG1  CB1
OG1  HOG1
OG1  CB1
CB1  HB1
CB1  CA1
HE2  CE2
NH11
NCA1
CA1  HA1
CA1  C1
CE2  CD2
CE2  CZ
HD2  CD2
OH   CZ
CD2  CG2
CZ   CE1
N2   C1
N2   CA2
C1   N3
HA33 CA3
CG2  CB2
CG2  CD1
CE1  HE1
CE1  CD1
CA2  CB2
CA2  C2
N3   CA3
N3   C2
CB2  HB2
CA3  C
CA3  HA32
CD1  HD1
C2   O3
CO

  [ impropers ]
CG2  CD1  CB2  CD2
CD1  CE1  CG2  HD1
CD2  CE2  CG2  HD2
CE2  CZ   CD2  HE2
CB2  CA2  CG2  HB2
CA2  N2   CB2  C2
C1   CA1  N2   N3
CA1  NC1   CB1
CA1  CB1  C1   HA1
CB1  OG1  CA1  CG1
CB1  CG1  CA1  HB1
C2   N3   CA2  O3
N3   C2   C1   CA3
CA3  CN3   HA33
CA3  HA33 N3   HA32
CZ   CE1  CE2  OH
CE1  CZ   CD1  HE1
CG1  HG11 CB1  HG12
CG1  HG11 CB1  HG13
; with next residue
C+N   CA3  O
; with previous residue
N-C   CA1  H11
[ cmap ]
-C  N  CA1  C1  N2
CA2 C2 N3 CA3 C

The only in that I not sure in that model is the corrections in the
cmap.itp which I added (I've used first two terms which are correspond
to the backbone atoms of the standart amino acid:
C NH1 CT1 C NH1 1 24 24\
C NH1 CT1 C N 1 24 24\
  and renamed it to the chromophore atom names)

by the way If you had had your rtp of the chromophore which you've
done in accordance to that paper could you provide me with them for
comparison with my model ?


James

2012/12/14, Justin Lemkul :



On 12/14/12 3:20 PM, James Starlight wrote:

Justin,

in the case of the system with the atom types assigned from that paper
the grompp produced above 118 errors of non standard bond, angle as
well as dihedral types ;o So it' seems that some 118 addition terms
must be added to the ffbonded.itp to the existing charmm parameters(
it's uncommon for me because in that case the atom names werefrom
standart charmm ff but the total number of errors was bigger than in
case of Swiss params non-standart names usage).



I'm not sure why there were so many errors when you used those
parameters.
Like
I said, we've used them before.  I recall a few errors along the way, but
manual
assignment of the bonded parameters according to the paper is fairly
straightforward.


By the way I've simulated choromophore produced by SWISS ( with the
charges assigned from the paper) in the vacuum and didnt notice any
inaccuracy in the conformation of chromophore. So the last that I
should is the carefull assignment of the 9 missed dihedral terms with
the rest of the protein.



Sounds like a reasonably approach.  Good luck.

-Justin

--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] Parametrisation of the cyclic nucleotides in Gromos force fields

2012-12-15 Thread Justin Lemkul



On 12/14/12 11:42 PM, James Starlight wrote:

The topology with the below params produced that 118 errors during
grompp processings ( after pdb2gmx processing the geoetry of the
mollecule was correct )

[CRN]
  [ atoms ]
CG2  CA-0.0900 0
CD1  CA-0.0800 1
CD2  CA-0.0800 2
CE1  CA-0.2800 3
CE2  CA-0.2800 4
CZ   CA 0.4500 5
NNH1   -0.4700 6
CA1  CPH1   0.1000 7
CB1  CT1   -0.1400 8
CG1  CT30.0900 9
OG1  OH1   -0.6600 10 ;!-0.6800
C1   CPH2   0.5000 11
N2   NR2   -0.6000 12
N3   NR1   -0.5700 13
C2   CPH1   0.5700 14
O3   O -0.5700 15
CA2  CPH1   0.1000 16
CA3  CPH10.1000 17
CC  0.5100 18
OO -0.5100 19
CB2  CE1   -0.1400 20
OH   O -0.6200 21
HA1  HB 0.0700 22
HA32 HB 0.0700 23
HA33 HB 0.0700 24
HD1  HP 0.1400 25
HD2  HP 0.1400 26
HE1  HP 0.1000 27
HE2  HP 0.1000 28
HG11 HA 0.0900 29
HG12 HA 0.0900 30
HG13 HA 0.0900 31
HOG1 H  0.4300 32
HB2  HA10.2100 33
H11  H  0.3700 34
HB1  HA10.2100 36
  [ bonds ]
HG11 CG1
HG12 CG1
CG1  HG13
CG1  CB1
OG1  HOG1
OG1  CB1
CB1  HB1
CB1  CA1
HE2  CE2
NH11
NCA1
CA1  HA1
CA1  C1
CE2  CD2
CE2  CZ
HD2  CD2
OH   CZ
CD2  CG2
CZ   CE1
N2   C1
N2   CA2
C1   N3
HA33 CA3
CG2  CB2
CG2  CD1
CE1  HE1
CE1  CD1
CA2  CB2
CA2  C2
N3   CA3
N3   C2
CB2  HB2
CA3  C
CA3  HA32
CD1  HD1
C2   O3
CO

  [ impropers ]
CG2  CD1  CB2  CD2
CD1  CE1  CG2  HD1
CD2  CE2  CG2  HD2
CE2  CZ   CD2  HE2
CB2  CA2  CG2  HB2
CA2  N2   CB2  C2
C1   CA1  N2   N3
CA1  NC1   CB1
CA1  CB1  C1   HA1
CB1  OG1  CA1  CG1
CB1  CG1  CA1  HB1
C2   N3   CA2  O3
N3   C2   C1   CA3
CA3  CN3   HA33
CA3  HA33 N3   HA32
CZ   CE1  CE2  OH
CE1  CZ   CD1  HE1
CG1  HG11 CB1  HG12
CG1  HG11 CB1  HG13
; with next residue
C+N   CA3  O
; with previous residue
N-C   CA1  H11
[ cmap ]
-C  N  CA1  C1  N2
CA2 C2 N3 CA3 C

The only in that I not sure in that model is the corrections in the
cmap.itp which I added (I've used first two terms which are correspond
to the backbone atoms of the standart amino acid:
C NH1 CT1 C NH1 1 24 24\
C NH1 CT1 C N 1 24 24\
  and renamed it to the chromophore atom names)

by the way If you had had your rtp of the chromophore which you've
done in accordance to that paper could you provide me with them for
comparison with my model ?



I gave the files to our collaborators some time ago and archived my own copies. 
 I don't have immediate access to them, sorry.


-Justin

--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] Parametrisation of the cyclic nucleotides in Gromos force fields

2012-12-15 Thread James Starlight
The last problem with which I've forced during preparation of my
chromophore is when I've defined bond between chromophore and the next
residue


C+N

That produce 15 addition errors about unknown UB and dihedral types
in the atoms of the next residue (not in the chromophore) where all UB
and impropers must be defined initially.
Why that occurs ?

James

2012/12/14, James Starlight :
> The topology with the below params produced that 118 errors during
> grompp processings ( after pdb2gmx processing the geoetry of the
> mollecule was correct )
>
> [CRN]
>  [ atoms ]
> CG2  CA-0.0900 0
> CD1  CA-0.0800 1
> CD2  CA-0.0800 2
> CE1  CA-0.2800 3
> CE2  CA-0.2800 4
> CZ   CA 0.4500 5
> NNH1   -0.4700 6
> CA1  CPH1   0.1000 7
> CB1  CT1   -0.1400 8
> CG1  CT30.0900 9
> OG1  OH1   -0.6600 10 ;!-0.6800
> C1   CPH2   0.5000 11
> N2   NR2   -0.6000 12
> N3   NR1   -0.5700 13
> C2   CPH1   0.5700 14
> O3   O -0.5700 15
> CA2  CPH1   0.1000 16
> CA3  CPH10.1000 17
> CC  0.5100 18
> OO -0.5100 19
> CB2  CE1   -0.1400 20
> OH   O -0.6200 21
> HA1  HB 0.0700 22
> HA32 HB 0.0700 23
> HA33 HB 0.0700 24
> HD1  HP 0.1400 25
> HD2  HP 0.1400 26
> HE1  HP 0.1000 27
> HE2  HP 0.1000 28
> HG11 HA 0.0900 29
> HG12 HA 0.0900 30
> HG13 HA 0.0900 31
> HOG1 H  0.4300 32
> HB2  HA10.2100 33
> H11  H  0.3700 34
> HB1  HA10.2100 36
>  [ bonds ]
> HG11 CG1
> HG12 CG1
> CG1  HG13
> CG1  CB1
> OG1  HOG1
> OG1  CB1
> CB1  HB1
> CB1  CA1
> HE2  CE2
> NH11
> NCA1
> CA1  HA1
> CA1  C1
> CE2  CD2
> CE2  CZ
> HD2  CD2
> OH   CZ
> CD2  CG2
> CZ   CE1
> N2   C1
> N2   CA2
> C1   N3
> HA33 CA3
> CG2  CB2
> CG2  CD1
> CE1  HE1
> CE1  CD1
> CA2  CB2
> CA2  C2
> N3   CA3
> N3   C2
> CB2  HB2
> CA3  C
> CA3  HA32
> CD1  HD1
> C2   O3
> CO
>
>  [ impropers ]
> CG2  CD1  CB2  CD2
> CD1  CE1  CG2  HD1
> CD2  CE2  CG2  HD2
> CE2  CZ   CD2  HE2
> CB2  CA2  CG2  HB2
> CA2  N2   CB2  C2
> C1   CA1  N2   N3
> CA1  NC1   CB1
> CA1  CB1  C1   HA1
> CB1  OG1  CA1  CG1
> CB1  CG1  CA1  HB1
> C2   N3   CA2  O3
> N3   C2   C1   CA3
> CA3  CN3   HA33
> CA3  HA33 N3   HA32
> CZ   CE1  CE2  OH
> CE1  CZ   CD1  HE1
> CG1  HG11 CB1  HG12
> CG1  HG11 CB1  HG13
> ; with next residue
> C+N   CA3  O
> ; with previous residue
> N-C   CA1  H11
> [ cmap ]
> -C  N  CA1  C1  N2
> CA2 C2 N3 CA3 C
>
> The only in that I not sure in that model is the corrections in the
> cmap.itp which I added (I've used first two terms which are correspond
> to the backbone atoms of the standart amino acid:
> C NH1 CT1 C NH1 1 24 24\
> C NH1 CT1 C N 1 24 24\
>  and renamed it to the chromophore atom names)
>
> by the way If you had had your rtp of the chromophore which you've
> done in accordance to that paper could you provide me with them for
> comparison with my model ?
>
>
> James
>
> 2012/12/14, Justin Lemkul :
>>
>>
>> On 12/14/12 3:20 PM, James Starlight wrote:
>>> Justin,
>>>
>>> in the case of the system with the atom types assigned from that paper
>>> the grompp produced above 118 errors of non standard bond, angle as
>>> well as dihedral types ;o So it' seems that some 118 addition terms
>>> must be added to the ffbonded.itp to the existing charmm parameters(
>>> it's uncommon for me because in that case the atom names werefrom
>>> standart charmm ff but the total number of errors was bigger than in
>>> case of Swiss params non-standart names usage).
>>>
>>
>> I'm not sure why there were so many errors when you used those
>> parameters.
>> Like
>> I said, we've used them before.  I recall a few errors along the way, but
>> manual
>> assignment of the bonded parameters according to the paper is fairly
>> straightforward.
>>
>>> By the way I've simulated choromophore produced by SWISS ( with the
>>> charges assigned from the paper) in the vacuum and didnt notice any
>>> inaccuracy in the conformation of chromophore. So the last that I
>>> should is the carefull assignment of the 9 missed dihedral terms with
>>> the rest of the protein.
>>>
>>
>> Sounds like a reasonably approach.  Good luck.
>>
>> -Justin
>>
>> --
>> 
>>
>> Justin A. Lemkul, Ph.D.
>> Research Scientist
>> Department of Biochemistry
>> Virginia Tech
>> Blacksburg, VA
>> jalemkul[at]vt.edu | (540) 231-9080
>> http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin
>>
>> 
>> --
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[gmx-users] Printing thermo data

2012-12-15 Thread John Doe

Hello All,

I was wondering if it's possible to print to a file different thermo data, such 
as force on atoms, pressure, bond energies, ect?

Thanks
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[gmx-users] different distance calculated by grompp and g_dist when doing umbrella sampling simulations

2012-12-15 Thread mircial
Dear All:

I encountered a problem when doing umbrella sampling. The distance calculated 
by grompp and g_dist is different, as shown by the following:

grompp  z component of g_dist(since I am constraining the distance between two 
groups along the z direction, I should calculate the z component of the 
distance, right?)
2.986   2.96
2.953   2.95
2.931   2.92
2.936   2.9355
2.844   2.83

There is an obvious difference between the distance calculated by the grompp 
and the g_dist, I also found that some post similar problems in the maillist, 
but I didn't found answers for the following questions.
(1)Why there is a such difference? 
(2)Also, does anyone know which value is used in the umbrella sampling 
simulations, the grompp result or the g_dist result?
(3)how to choose the right starting conformations since there is such a 
difference? 

I also pasted the pull code I used as follows:

pull=   umbrella
pull_geometry   =   direction
pull_dim=   N N Y
pull_start  =   yes
pull_nstxout=   500
pull_nstfout=   500
pull_ngroups= 1
pull_group0 =   Protein
pull_group1 =   AMA
pull_init1  =   0 
pull_rate1  =   0.000;nm/ps
pull_k1 =   4500 ;kJ/mol/nm^2


Thanks in advance!!

Best regards,
Ruo-Xu Gu
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