[gmx-users] Grompp error: No default g96angle type

[shahid nayeem]

Dear All
I used the following command sequentially to prepare file for energy
minimization and subsequent MD run.
1. pdb2gmx  -f *.pdb -o seq.gro -p seq.top
2. editconf -f seq.gro -o seq_box.gro -d 1.0 -bt cubic
3. genbox   -cp seq_box.gro -cs spc216.gro -o seq_b4ion.gro -p seq.top
4. grompp   -c seq_b4ion.gro -p seq.top -o seq_b4ion.tpr -f em.mdp
grompp gives following error.processing topology...
Opening library file /usr/local/gromacs/share/gromacs/top/ffG43a1.itp
Opening library file /usr/local/gromacs/share/gromacs/top/ffG43a1nb.itp
Opening library file /usr/local/gromacs/share/gromacs/top/ffG43a1bon.itp
Opening library file /usr/local/gromacs/share/gromacs/top/ff_dum.itp
Generated 279 of the 1225 non-bonded parameter combinations

ERROR 1 [file seq.top, line 1965]:
  No default G96Bond types


ERROR 2 [file seq.top, line 5271]:
  No default G96Angle types


ERROR 3 [file seq.top, line 5272]:
  No default G96Angle types


ERROR 4 [file seq.top, line 5648]:
  No default G96Angle types


ERROR 5 [file seq.top, line 5653]:
  No default G96Angle types


ERROR 6 [file seq.top, line 5654]:
  No default G96Angle types


ERROR 7 [file seq.top, line 5655]:
  No default G96Angle types


ERROR 8 [file seq.top, line 5656]:
  No default G96Angle types


ERROR 9 [file seq.top, line 6201]:
  No default Proper Dih. types

Opening library file /usr/local/gromacs/share/gromacs/top/spc.itp
Opening library file /usr/local/gromacs/share/gromacs/top/ions.itp
Excluding 3 bonded neighbours molecule type 'Protein_A'
Excluding 2 bonded neighbours molecule type 'SOL'
Excluding 2 bonded neighbours molecule type 'SOL'

NOTE 1 [file seq.top, line 6932]:
  System has non-zero total charge: 7.000001e+00



processing coordinates...
double-checking input for internal consistency...
renumbering atomtypes...
converting bonded parameters...

There was 1 note

-------------------------------------------------------
Program grompp, VERSION 4.0.7
Source code file: grompp.c, line: 986

Fatal error:
There were 9 errors in input file(s)
-------------------------------------------------------
  pdb2gmx works properly using ff43a1 forcefield. My protein contains
Heme. I was having N-terminal ACE group which I simply deleted from
the pdb.
Am I right in deleting this group. How should I proceed to get rid of
this error.

Thanks in anticipation of help.
Shahid Nayeem