Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-27 Thread Justin Lemkul
On 7/27/12 8:50 AM, J Peterson wrote: Hi Justin, Thanks for that information. I also would like to confirm with you that should I combine my metal ion too while I combine Protein and POPC into Protein_POPC group to be used in COMM removal? So that I will have a group Protein_HEM_POPC. With

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-24 Thread Justin Lemkul
On 7/24/12 2:49 AM, J Peterson wrote: Thanks for that comment. I've another query during inflating step in Justin's tutorial. In my case, during the inflation, 4 lipids from the upper and 2 lipids from the lower leaflets were removed. Would there be a problem in this sort non-uniform deletion

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-23 Thread Mark Abraham
On 24/07/2012 2:57 PM, J Peterson wrote: Hi Justin, That works really fine and thanks. Now, how can I add additional SOL molecules only one side of the bilayer (either upper or lower)? Since my protein binds at the outer side (extracellular region) of the membrane I can only fill the upper (ext

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-23 Thread Justin Lemkul
On 7/23/12 7:53 AM, J Peterson wrote: Thank you so much for that, Justin. Now I could expand the bilayer. I've another query. My protein has a small N-terminal portion embedded in the membrane, I would like to insert only this part into the membrane during 'packing the lipid around the protei

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-23 Thread Justin Lemkul
On 7/23/12 5:31 AM, J Peterson wrote: Hi Justin, Thanks for all your help to get me through membrane simulations. I've a problem to be solved. I need a long and thick membrane to simulate a big protein. The longest bilayer that I can download from Tieleman's website is 64 molecules long. How

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-17 Thread Justin Lemkul
On 7/17/12 4:05 AM, J Peterson wrote: Hi Justin, I have the following Notes during NPT equilibration. NOTE 1 [file pr_NPT.mdp]: nstcomm < nstcalcenergy defeats the purpose of nstcalcenergy, setting nstcomm to nstcalcenergy http://manual.gromacs.org/online/mdp_opt.html#out nstcalcene

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-13 Thread Justin A. Lemkul
On 7/13/12 6:44 AM, J Peterson wrote: Thanks Justin, The explanations are very very useful during my course of simulating a protein with POPC. I also would like to get explanation on how to simulate a protein which has only its N-terminal region embedded in the membrane but the rest in solven

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-13 Thread Justin A. Lemkul
On 7/13/12 4:14 AM, J Peterson wrote: Hi Justin, I have another doubt on the strong posres that was included in the topology file. When do we need to remove that position restraint? Does it really affect at point of time the system? The strong restraints are only needed for InflateGRO. Dur

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-13 Thread Justin A. Lemkul
On 7/13/12 1:44 AM, J Peterson wrote: Thanks for the comment. By the way how to make a bigger box at this time of the tutorial without affecting any part of the system. Can I use editconf with slightly bigger number for z-axis (something like 6.7 which was 5.7 before)? The box should be suff

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-12 Thread Justin A. Lemkul
On 7/13/12 12:24 AM, J Peterson wrote: Hi Justin, I followed your comments and now at the stage of adding solvents. I wonder to see the protein after shrinking step to have no SOL molecules as there were SOL molecules in the source popc128b.pdb. Had we removed all the original SOL molecules an

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-12 Thread Justin A. Lemkul
On 7/12/12 10:23 PM, J Peterson wrote: Hi Justin, Thanks for the suggestion I got it solved somehow. The main problem was in the popc128b.pdb itself, it has first 64 lipids and half of the SOl molecules followed by rest of the POPC and SOL molecules. When I rearranged them the error was solved

Re: [gmx-users] Re: Error in Membrane simulations with POPC bilayer

2012-07-12 Thread Justin A. Lemkul
On 7/12/12 4:59 AM, J Peterson wrote: Hi Justin, Thanks for the effort to help me. I still no out of the error. The following is the content of my topol_popc.top ; Include chain topologies #include "gromos53a6_lipid.ff/forcefield.itp" #include "popc.itp" ; Include water topology #include "g