Re: [gmx-users] Regarding ffG43a1p force field

2011-06-23 Thread Ramachandran G
fine then I think you can deposit it in User contributions in gromacs repository... On Thu, Jun 23, 2011 at 2:38 PM, Ramachandran G gtr...@gmail.com wrote: Why you are doing simulation without chromophore? Chromophore is important in GFP. If you want i can send you the forcefield which i am

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-23 Thread Ramachandran G
For the GFP chromophore i name residue as CRIH. 1. aminoacids.rtp CB2 CB 0.019103 1 CA2 CC-0.026635 2 N2 NB-0.436463 3 C1 CC 0.302706 4 N3 NB-0.541478 5 C2 C 0.563844

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-23 Thread Ramachandran G
CC C4 180.04.1840 2 NBCCCCT 4 180.04.1840 2 CACBCA CA 4 180.04.1840 2 CAHACA CA 4 180.04.1840 2 ; added to test N CT CH4 180.04.1840 2 On Thu, Jun 23, 2011 at 12:13 AM, Ramachandran G gtr

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-23 Thread Ramachandran G
On Thu, Jun 23, 2011 at 12:18 AM, Ramachandran G gtr...@gmail.com wrote: For ffbonded.itp, i added the following. (you need to be carefull here since i cooked upto the force constants) C CCCBCA9 180.0 4.309 1 NBCCC O 9 180.0 4.309 1 ; NB

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-23 Thread Ramachandran G
yes! On Thu, Jun 23, 2011 at 12:26 AM, bharat gupta bharat.85.m...@gmail.comwrote: these are in continuity I mean for the ffbonded.itp file On Thu, Jun 23, 2011 at 4:21 PM, Ramachandran G gtr...@gmail.com wrote: more parameters - ffbonded.itp NBCT 10.1444294553.6 NBC

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-23 Thread Ramachandran G
...@gmail.comwrote: Is is this for the neutral chromophore or protonated one ?? On Thu, Jun 23, 2011 at 4:29 PM, Ramachandran G gtr...@gmail.com wrote: yes! On Thu, Jun 23, 2011 at 12:26 AM, bharat gupta bharat.85.m...@gmail.comwrote: these are in continuity I mean for the ffbonded.itp file On Thu

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-22 Thread Ramachandran G
Hi Bharat, I used Amber force field, but still i am not statisfied with the parameters which i used because after some nanosecond simulation(1 -2 ns) the planarity of the sturcture changes. I tired changing the force constant but still not much successfull. If you got success please let me

Re: [gmx-users] Regarding ffG43a1p force field

2011-06-22 Thread Ramachandran G
the chromophore. So, planarity does not matter to be .. On Thu, Jun 23, 2011 at 2:23 PM, Ramachandran G gtr...@gmail.com wrote: Hi Bharat, I used Amber force field, but still i am not statisfied with the parameters which i used because after some nanosecond simulation(1 -2 ns) the planarity

[gmx-users] monitoring the water molecules

2011-06-16 Thread Ramachandran G
Hi gmx-users. I am doing MD simulation with the green fluorescent protein, where confined water molecules exist inside the protein barrel. During the coarse of the simulation i noticed these confined water molecule get exchange with outside bulk water. Is it possible to monitor or mark the

[gmx-users] recovering topology

2011-05-18 Thread Ramachandran G
Hi gmx-users: Is it possible to recover the topology from cpt file, it is so.. how and what command i need to use? Thanks Rama -- gmx-users mailing listgmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users Please search the archive at

[gmx-users] decomposing the energy

2011-05-14 Thread Ramachandran G
Hello gmx users: I did 1ns simulation for my system and have the trajectory and energy files. Now i want to see the energy of some specific residues. So, i decompose(separated) the energy groups and edited the mdp file. Using the mdp file, i created a new tpr file and rerun the mdrun using

[gmx-users] PYP chromophore force field

2011-04-20 Thread Ramachandran G
Hi gromacs users, I am working on Photo active yellow protein. Although i successfully build the force field and patched the chromophore to the protein. After energy minimizing the protein, the chromophore flies away separately. I don't know whether i am missing anything? Please help.

Re: [gmx-users] PYP chromophore force field

2011-04-20 Thread Ramachandran G
that is covalently bound to the protein backbone via a thiol-ester cysteine linkage Cys-69... Maybe you forgot to specify a covalent bond in your topology... On 2011-04-20 06:46:54PM -0500, Ramachandran G wrote: Hi gromacs users, I am working on Photo active yellow protein. Although i

[gmx-users] view the vibrational modes

2011-02-03 Thread Ramachandran G
Hi gmx-users, Is there is any software available to view the vibrational modes selectively for particular wave number from the trajectory file. Thanks and regards, Rama -- gmx-users mailing listgmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users Please search the

Re: [gmx-users] extending the simulation with modified mdp option

2011-01-13 Thread Ramachandran G
gen_vel = no ; generate initial velocities ;gen_temp= 300.0 ; initial temperature ;gen_seed= 173529; random seeD Please help. thank you, Rama On Wed, Jan 12, 2011 at 3:06 PM, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Hi gmx-users

Re: [gmx-users] extending the simulation with modified mdp option

2011-01-13 Thread Ramachandran G
Hi Mark, Justin, Thanks for your help. The details are helpful to improve my MD simulation. Also i need update my gromacs version from 4.5.1 to 4.5.3. Thanks again, Rama On Thu, Jan 13, 2011 at 3:47 PM, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: thanks for your reply

[gmx-users] extending the simulation with modified mdp option

2011-01-12 Thread Ramachandran G
Hi gmx-users, I tried extending one of simulation with modified mdp option. First i used the command, grompp -f new.mdp -c old.tpr -o new.tpr then i used the command to extend tpbconv -s new.tpr -extend timetoextendby -o next.tpr Then, mdrun -s next.tpr -cpi previous.cpt I surprised to

[gmx-users] g_mindist

2011-01-03 Thread Ramachandran G
Hi Gromacs users, I used g_mindist to calculate the minimum distance between a residue and a group of water molecules. Since distance is a length between two points in space, for the program considers the bunch of water molecules(15 number) what specific point does the group consider ? Thank

Re: [gmx-users] md.log

2010-12-14 Thread Ramachandran G
for extension. Use something like: grompp -f md_extension.mdp -c MD_01.gro -n system.ndx -p system.top -t MD_01.trr -r MD_01.edr -o MD_02.tpr Itamar On 14/12/10 1:29 PM, Ramachandran G wrote: Hi gmx-users:     I am trying to extend my simulation run but unfortunately i deleted the file md.log

[gmx-users] md.log

2010-12-13 Thread Ramachandran G
Hi gmx-users: I am trying to extend my simulation run but unfortunately i deleted the file md.log. Is there any way i get my md.log file using the existing .edr or .trr files so that i can proceed further. Thank you. Rama -- gmx-users mailing listgmx-users@gromacs.org

Re: [gmx-users] md.log

2010-12-13 Thread Ramachandran G
On 14/12/10 1:29 PM, Ramachandran G wrote: Hi gmx-users:     I am trying to extend my simulation run but unfortunately i deleted the file md.log. Is there any way i get my md.log file using the existing .edr or .trr files so that i can proceed further. Thank you. Rama -- In theory

Re: [gmx-users] GFP chromophore topology help

2010-11-13 Thread Ramachandran G
: Ramachandran G wrote: Thank you for the help.       I have successfully constructed the chromphore molecule but still have problem in connecting it to the neigbhouring residues. I don't know how the connection sequence needs to be given in gromacs. Please help You stand a much better chance

Re: Subject: Re: [gmx-users] GFP chromophore topology help

2010-11-13 Thread Ramachandran G
Thank you, Yes, i did energy minimization to the chromophore alone and it stays stable The problem arise when i do the energy minimization to the GFP-chromophore full system. It clearly shows the atoms which is expected to connect the negihbouring residues is flying apart. I am still

Re: [gmx-users] GFP chromophore topology help

2010-11-12 Thread Ramachandran G
, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Dear gromacs users:        I have constructed the Amber03 force fields parameters (bonds,angles, proper and imporer dihedral.) for the chromophore (p-hydroxybenzylidene-imidazolinone) inside GFP system and got the topology

[gmx-users] GFP chromophore topology help

2010-11-12 Thread Ramachandran G
A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Dear gromacs users:        I have constructed the Amber03 force fields parameters (bonds,angles, proper and imporer dihedral.) for the chromophore (p-hydroxybenzylidene-imidazolinone) inside GFP system and got the topology

[gmx-users] GFP chromophore topology help

2010-11-09 Thread Ramachandran G
Dear gromacs users: I have constructed the Amber03 force fields parameters (bonds,angles, proper and imporer dihedral.) for the chromophore (p-hydroxybenzylidene-imidazolinone) inside GFP system and got the topology. But after energy minimization of the system, the conformation of the

Re: [gmx-users] Re: eigenvectors in readable format

2010-10-16 Thread Ramachandran G
indicates the eigenvector index. Make sure not to use any options like pbc/fitting :p Cheers, Tsjerk On Sat, Oct 16, 2010 at 7:00 AM, Ramachandran G gtr...@gmail.com wrote: Hi, Can anyone help to get the eigen vector in ascii format. I have with me the trajectory file 'eigenvec.trr

[gmx-users] eigenvectors in readable format

2010-10-15 Thread Ramachandran G
Hi gmx users: I did normal mode analysis and got the hessian.mtx . Using the command g_nmeig_d on the hessian.mtx i got the eigenfreq.xvg, eigenval.xvg, eigenvec.trr. I need the complete eigenvector in the readable format. How i can get it? Thank you. with regards, Rama -- Postdoctoral

[gmx-users] Re: eigenvectors in readable format

2010-10-15 Thread Ramachandran G
(readable) format of eigenvector and hessian.mtx . Your help is highly appreciated. Thank you. with regards, Rama On Fri, Oct 15, 2010 at 2:29 PM, Ramachandran G gtr...@gmail.com wrote: Hi gmx users: I did normal mode analysis and got the hessian.mtx . Using the command g_nmeig_d

Re: [gmx-users] Problem with pdb2gmx and a new residue

2010-09-20 Thread Ramachandran G
Hi Justin, Presently i too facing the same exact problem. I built the topology for a chromophore in the protein and entered all the new parameters in the .rtp, atp, hdb and defined the bonded and nonbonded parameters. Finally i got the following error. Fatal error: Atom OXT in residue CRIH 64

[gmx-users] unit conversions

2010-09-17 Thread Ramachandran G
Hi gmx-users, I would like to know the units conversion of epsilon, sigma (from non-bonded, Van der Waal interaction) from Charmm or MOIL to gromacs. Thank you. with regards, Rama -- gmx-users mailing listgmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users Please

Re: [gmx-users] unit conversions

2010-09-17 Thread Ramachandran G
PM, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Hi gmx-users, I would like to know the units conversion of epsilon, sigma (from non-bonded, Van der Waal interaction) from Charmm or MOIL to gromacs. Thank you. My guess would be that each of the respective manuals

Re: [gmx-users] unit conversions

2010-09-17 Thread Ramachandran G
PM, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: I understood from the gromacs manual the units for epsilon and sigma are KJ/mol and nm and the corresponding units in MOIL Kcal/mol and Angstom. But when i checked for some atoms, the epsilon values are not matching. i.e

Re: [gmx-users] unit conversions

2010-09-17 Thread Ramachandran G
Thank you for your clarification. Rama On Fri, Sep 17, 2010 at 5:49 PM, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Thank you Justin, You are right i am not comparing the same force field. But i am still curious to know the conversion factor for epsilon from MOIL

[gmx-users] atom type parameters

2010-09-13 Thread Ramachandran G
Dear gmx-users: I am trying to get the topology for a chromophore exist in the Green fluoresent protein. Although to some extent i got success in building the parameters in the 'ff*.rtp' file, i got struck in building 'atom type parameter' ( ff*.atp). I am trying to use Charmm force

[gmx-users] tip5p in ffcharmm

2010-07-18 Thread Ramachandran G
Hi gmx users, Since i wanted to use 'TIP5P' water model along with charmm forcefield, i modified the 'tip5p.itp' file according to other existing force field in gromacs And i have made the following changes in the 'ffcharmm27_ffnb.itp' #ifdef HEAVY_H OWT58 9.9514000.0

Re: [gmx-users] amber/charmm force field and HB lifetime at low temperature

2010-07-12 Thread Ramachandran G
. Your help will be highly appreciated. Thank you. Yours sincerely, Rama On Wed, Jun 30, 2010 at 8:30 PM, Mark Abraham mark.abra...@anu.edu.auwrote: - Original Message - From: Ramachandran G gtr...@gmail.com Date: Thursday, July 1, 2010 11:42 Subject: [gmx-users] amber/charmm force

[gmx-users] amber/charmm force field and HB lifetime at low temperature

2010-06-30 Thread Ramachandran G
Hi gromacs users: Using amber/charmm force field we simulated a solvated protein system at different temperature(300,250 and 200K). I used TIP5P water model and applied NVT ensemble . We analyzed the hydrogen bond life time correlation function(HBCF) to study the protein water interactions.

[gmx-users] tip5p in ffcharmm

2010-05-23 Thread Ramachandran G
Dear gromacs users, I could not able to use tip5p water model with charmm force field. If anybody tried successfully, please help me. Thank you. with regards, Rama -- gmx-users mailing listgmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users Please search the

[gmx-users] 'SHAKE' : gromacs 4.0.7

2010-04-20 Thread Ramachandran G
Hello gromacs users: I installed the new version of gromacs and tried to run 'mdrun_mpi' in parrallel but it gives the error pasted below. When i switched the constrain from 'shake' to 'lincs' it runs. I know 'shake' algorithm compilation was done but i don't why i am getting this

[gmx-users] Re: ffcharmm27 for HEME

2010-04-15 Thread Ramachandran G
have now added the charmm files to git head and the protein and lipid parts should work at least. Simply check out the latest git and the charmm parameters should show up in pdb2gmx. /Pär 11 mar 2010 kl. 03.04 skrev Ramachandran G: Hello Bjelkumar, Thanks for your reply. I will wait

Re: [gmx-users] Re: ffcharmm27 for HEME

2010-04-15 Thread Ramachandran G
...@cbr.su.se wrote: Hi, 15 apr 2010 kl. 11.11 skrev Ramachandran G: Hello Par: Using the latest git i could able to work on my oxy-hemoglobin system with new gromacs version 4.0.5 successfully. CHARMM is not supportd in version 4.0.5, you probably mean the developer version? But since my

Re: [gmx-users] NVE mdp

2010-04-01 Thread Ramachandran G
...@anu.edu.auwrote: On 31/03/2010 2:51 PM, Ramachandran G wrote: Dear gromacs users: I am using following mdp file as input for simulating the system with NVE ensemble. But when i check the 'Total energy', it doesn't seems to remain constant and keep decreasing. I am also Thus, you

[gmx-users] NVE mdp

2010-03-30 Thread Ramachandran G
Dear gromacs users: I am using following mdp file as input for simulating the system with NVE ensemble. But when i check the 'Total energy', it doesn't seems to remain constant and keep decreasing. I am also giving some part of my output. Thanks for your help Rama title=

Re: [gmx-users] correlation function 'time value' ?

2010-03-01 Thread Ramachandran G
Dear Mark and David, Thanks you, i will check the paper very carefully and try again. regards, Rama On Sat, Feb 27, 2010 at 1:13 AM, Mark Abraham mark.abra...@anu.edu.auwrote: On 27/02/2010 7:31 PM, Ramachandran G wrote: Dear Dr. van der Spoel: Thanks for the clarification in your

Re: [gmx-users] correlation function 'time value' ?

2010-02-27 Thread Ramachandran G
, and/or is it possible to customize the t in gromacs? best Rama On Fri, Feb 26, 2010 at 10:03 PM, David van der Spoel sp...@xray.bmc.uu.sewrote: On 2010-02-27 03.27, Ramachandran G wrote: Hi gromacs users: As you know autocorrelation function C(t) C(t) = f(0).f(t

[gmx-users] correlation function 'time value' ?

2010-02-26 Thread Ramachandran G
Hi gromacs users: As you know autocorrelation function C(t) C(t) = f(0).f(t) 't' value can start from 0 but, i would like to know what value does gromacs use, more specifically for g_hbond. Can anyone help me? Thank you. Rama -- gmx-users

[gmx-users] charmm force field and 'HEME' group

2010-02-22 Thread Ramachandran G
Dear gromacs users: I am trying to use ffcharmm27 patched with gromacs, since it does not have 'heme' i tried add it manually but still i am getting error while doing pdb2gmx. If anybody have already done 'HEME' protein using charmm force field in gromacs, please help me. Thanks Rama --

[gmx-users] oxy hemoglobin

2010-02-08 Thread Ramachandran G
Dear gromacs users: I am trying to get the topology file for oxy-hemoglobin. As suggested below in the link below, I am trying to modify my itp or rtp file. http://osdir.com/ml/science.biology.gromacs.user/2006-07/msg00236.html But, if anybody has already constructed rtp file for oxy

[gmx-users] stretched exponential

2010-01-26 Thread Ramachandran G
Dear gromacs users: I have a couple of questions: While doing auto correlation function under what condition i need to use polynomials? Apart from the fit functions existing in the gromacs how can i use different functions like stretched exponential in the form

Re: [gmx-users] splitting a trajectory

2009-12-11 Thread Ramachandran G
Thanks, it works when i give proper time. Previously i made mistake by giving the time frame number. Rama On Thu, Dec 10, 2009 at 9:13 PM, Justin A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Thanks for your help. I have tried the command trjconv -f traj.trr -s AFP-500ps.tpr

[gmx-users] tip5p water model topology

2009-12-11 Thread Ramachandran G
Dear gmx users, I have created a water box using tip5p model and trying to get the topology file for that using pdb2gmx but, i couldn't able to create the topology file and i got the error message Fatal error: Atom OL1 in residue HO5 1 not found in rtp entry with 5 atoms

[gmx-users] g_velacc problem

2009-12-10 Thread Ramachandran G
Hi all, I am trying to do velocity auto-correlation function(VACF) for the 'oxygen atom' present in a 63 Ang. cubic water box, simulated upto 500ps. And the velocities are stored at every 5fs. While doing the analysis(g_velacc), it got struck at 400ps, since if felt it is mainly due to the

[gmx-users] splitting a trajectory

2009-12-10 Thread Ramachandran G
Dear gromacs users: Can any one tell me how can i split a trajectory file from a specific time interval of my interest. For example if i have a trajectory file up to 0-100ps, and my interest is to consider part of the trajectory from 50-75ps, how i can go about it either by splitting the

Re: [gmx-users] splitting a trajectory

2009-12-10 Thread Ramachandran G
A. Lemkul jalem...@vt.edu wrote: Ramachandran G wrote: Dear gromacs users: Can any one tell me how can i split a trajectory file from a specific time interval of my interest. For example if i have a trajectory file up to 0-100ps, and my interest is to consider part of the trajectory

[gmx-users] system blowing

2009-11-14 Thread Ramachandran G
Dear all, I am trying to minimize a protein structure but i noticed initially before it starts minimization, it gives warning - Warning: 1-4 interaction between 1434 and 1490 at distance 1.783 which is larger than the 1-4 table size 1.000 nm These are

[gmx-users] force field: heme group

2009-11-11 Thread Ramachandran G
Dear all, It is known that force field for the heme group doesn't exist in gromacs. So i tried to use amber force fields(AMBER94, AMBER99, AMBER99p, AMBER03, AMBERGS, AMBERGSs) by patching with my latest gromacs version 4.0.5 but still it gives the error message 'Residue 'HEME' not found

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-11-09 Thread Ramachandran G
,t,natoms,x,box)); */ } while(read_next_frame(status,fr)); close_trj(status); if (out != -1) close_trx(out); if (fp) ffclose(fp); thanx(stderr); return 0; } On Mon, Nov 2, 2009 at 9:41 PM, Mark Abraham mark.abra...@anu.edu.au wrote: Ramachandran G wrote: Yes, i do write

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-11-02 Thread Ramachandran G
. Regards, Rama On Sat, Oct 31, 2009 at 11:43 PM, David van der Spoel sp...@xray.bmc.uu.se wrote: Ramachandran G wrote: Dear David,      Thank you for you help. It is very much helpful for me. I have one more question. Is it possible to create index file for the oxygen atom or water molecules alone

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-11-02 Thread Ramachandran G
. Rama On Mon, Nov 2, 2009 at 6:36 PM, Mark Abraham mark.abra...@anu.edu.au wrote: Ramachandran G wrote: Thank you, I have installed new version of gromacs4.0.5 and trjorder works fine in giving me the trajectory file(ordered.trr)  but using this file when i try  g_velacc(velocity

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-11-01 Thread Ramachandran G
...@xray.bmc.uu.se wrote: Ramachandran G wrote: I have used the option as follows:   g_hbond -f  file.trr -s file.tpr -n file.ndx -ac output.xvg -life koko.xvg To find the continious HB-correlation function, what option should i need to use. Thank you for your help. Rama On Tue, Oct 6, 2009 at 11

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-11-01 Thread Ramachandran G
:43 AM, David van der Spoel sp...@xray.bmc.uu.se wrote: Ramachandran G wrote: Dear David,      Thank you for you help. It is very much helpful for me. I have one more question. Is it possible to create index file for the oxygen atom or water molecules alone exist in a hydration shell. Thank

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-10-07 Thread Ramachandran G
: Ramachandran G wrote: Thank you for the reference. But still i like check it out for my system.  But still i don't know how to get 'S' type hydrogen bonding. I am pasting my screen output below: You need to pass the -life option

[gmx-users] S-type Hydrogen bond correlation function

2009-10-06 Thread Ramachandran G
Dear gromacs users: I like to know whether gromacs will calculate S-type hydrogen bond correlation function? If it so how it can be done? Thank you. Rama ___ gmx-users mailing listgmx-users@gromacs.org

Re: [gmx-users] S-type Hydrogen bond correlation function

2009-10-06 Thread Ramachandran G
you. Rama On Tue, Oct 6, 2009 at 3:06 AM, David van der Spoel sp...@xray.bmc.uu.se wrote: Ramachandran G wrote:              C_HB(T)  =  h(t)h(T+t)/ h(t)              S_HB(T)  =  h(t)H(T+t)/h(t)                   h(T)  =  1, if a pair of atoms bonded at time T,                          =  0