[gmx-users] Membrane issues

[Haerterich, Steffen]

Dear all,
after browsing around the manual and mailing list archive I am rather
confused about which forcefield to use for a protein/water/bilayer 
simulation. 

The standard GROMACS or the ffgmx43a2x?

Another problem: The lipid.itp from Tieleman is said to be included 
within the GROMACS-Forcefield. There also exists a building block for 
DPPC. However there are no bonds specified within the ffgmx.itp for 
CH3-NL as should be (these are used in the DPPC building block). 
The same is true for some angles.
On the other hand the dppc.itp file alone does not work as #include 
within the topology-file for some atom types are not defined. So there 
are some atomtypes being defined twice with the lipid.itp included 
and others missing without the lipid.itp.

Is this true or did I just stupidly oversee some major detail?
Is there some "ready to use" and easy way to build a nice little bilayer?

Thanks a lot for your answers.

S.H.