[gmx-users] problem with membrane simulation

[free882 at inwind.it]

hi all,
I'm trying to do a simulation of a membrane protein in DPPC, with Gromacs4.6. 
I used gromos96 53a6 as forcefield. I'm following KALP15 tutorial of gromacs.
I'm trying to orient protein in membrane but I can't with editconf because I 
don't know what parameters I had to use as center of mass. 
I've tried to move the membrane in the correct orientation with vmd but when I 
do the energy minimization, the membrane change position.
how to fix it? 
thank you for help