[gmx-users] pdb2gmx fatal error

Ali Khodayari ali.khodayari at student.kuleuven.be
Thu Nov 8 19:37:21 CET 2018


Dear Justin,

Thank you for your response. Yet, I have not been able to solve the problem.

The structure looks fine but gromacs is complaining about a dangling atom at
one of the terminal ends, if I choose no terminal to be added. While,
assigning a terminal to the ends (which I don't understand why), results to
another error, which to me seems bizarre. It is still complaining about an
atom (C6) which is not found in the input file (.rtp?), however, it is
indeed one of the atoms in the rtp file. 
Here is what it looks like in the rtp file:

[ GLC0 ]
 [ atoms ]
   C4   CH1R    0.23200     1   
   O4   OA     -0.64200     1
   HO4  H       0.41000     1
   C3   CH1R    0.23200     2
   O3    OA    -0.64200     2
  HO3     H     0.41000     2
   C2   CH1R    0.23200     3
   O2    OA    -0.64200     3
  HO2     H     0.41000     3
   C6   CH2     0.23200     4
   O6    OA    -0.64200     4
  HO6     H     0.41000     4
   C5   CH1R    0.23200     0
   O5    OR    -0.46400     0
   C1   CH1R    0.46400     0
   O1    OE    -0.46400     0

And the pdb input file is:

ATOM      1  C1  GLC0    1      3.992   3.199   3.177  1.00  0.04
C    
ATOM      2  C2  GLC0    1      3.597   2.204   2.072  1.00  0.04
C    
ATOM      3  C3  GLC0    1      4.231   2.633   0.737  1.00  0.04
C    
ATOM      4  C4  GLC0    1      3.713   4.036   0.378  1.00  0.04
C    
ATOM      5  C5  GLC0    1      4.096   5.017   1.502  1.00  0.04
C    
ATOM      6  C6  GLC0    1      3.581   6.419   1.132  1.00  0.04
C    
ATOM      7  O2  GLC0    1      4.094   0.828   2.442  1.00  0.04
O    
ATOM      8  O5  GLC0    1      3.476   4.569   2.805  1.00  0.04
O    
ATOM      9  O6  GLC0    1      4.207   6.834  -0.178  1.00  0.04
O    
ATOM     10  H1  GLC0    1      5.128   3.219   3.268  1.00  0.00
H    
ATOM     11  H2  GLC0    1      2.462   2.181   1.967  1.00  0.00
H    
ATOM     12  H3  GLC0    1      5.366   2.661   0.847  1.00  0.00
H    
ATOM     13  H4  GLC0    1      2.578   4.005   0.271  1.00  0.00
H    
ATOM     14  H5  GLC0    1      5.230   5.045   1.611  1.00  0.00
H    
ATOM     15  H61 GLC0    1      3.858   7.165   1.950  1.00  0.00
H    
ATOM     16  H62 GLC0    1      2.449   6.385   1.015  1.00  0.00
H    
ATOM     17  HO2 GLC0    1      5.198   0.853   2.551  1.00  0.00
H    
ATOM     18  HO6 GLC0    1      5.313   6.850  -0.083  1.00  0.00
H    
ATOM     19  O4  GLC0    2      4.312   4.595   9.824  1.00  0.04
O    
ATOM     20  C1  GLC0    2      3.708   4.145   8.515  1.00  0.04
C    
ATOM     21  C2  GLC0    2      4.109   5.126   7.399  1.00  0.04
C    
ATOM     22  C3  GLC0    2      3.497   4.668   6.062  1.00  0.04
C    
ATOM     23  C4  GLC0    2      4.005   3.250   5.730  1.00  0.04
C    
ATOM     24  C5  GLC0    2      3.616   2.295   6.877  1.00  0.04
C    
ATOM     25  C6  GLC0    2      4.151   0.877   6.596  1.00  0.04
C    
ATOM     26  O2  GLC0    2      3.601   6.506   7.743  1.00  0.04
O    
ATOM     27  O3  GLC0    2      3.909   5.661   5.002  1.00  0.04
O    
ATOM     28  HO4 GLC0    2      4.850   3.729  10.263  1.00  0.00
H    
ATOM     29  O1  GLC0    1      3.396   2.685   4.467  1.00  0.04
O    
ATOM     30  O5  GLC0    2      4.225   2.770   8.173  1.00  0.04
O    
ATOM     31  O6  GLC0    2      3.558   0.309   5.328  1.00  0.04
O    
ATOM     32  H1  GLC0    2      2.572   4.115   8.609  1.00  0.00
H    
ATOM     33  H2  GLC0    2      5.244   5.151   7.307  1.00  0.00
H    
ATOM     34  H3  GLC0    2      2.361   4.651   6.153  1.00  0.00
H    
ATOM     35  H4  GLC0    2      5.141   3.258   5.636  1.00  0.00
H    
ATOM     36  H5  GLC0    2      2.480   2.262   6.979  1.00  0.00
H    
ATOM     37  H61 GLC0    2      3.879   0.196   7.468  1.00  0.00
H    
ATOM     38  H62 GLC0    2      5.286   0.920   6.494  1.00  0.00
H    
ATOM     39  HO2 GLC0    2      2.496   6.480   7.836  1.00  0.00
H    
ATOM     40  HO3 GLC0    2      5.015   5.674   4.919  1.00  0.00
H    
ATOM     41  HO6 GLC0    2      2.453   0.270   5.418  1.00  0.00
H    
ATOM     42  O3  GLC0    1      3.852   1.653  -0.348  1.00  0.00
O    
ATOM     43  HO3 GLC0    1      4.305   1.969  -1.311  1.00  0.00
H    
END

The error is given as a result of the command:  gmx pdb2gmx -f
cellobiose.pdb -o cellobiose.gro -ignh -ter

The error:
Fatal error:
Residue 4 named GLC0 of a molecule in the input file was mapped
to an entry in the topology database, but the atom C6 used in
that entry is not found in the input file. Perhaps your atom
and/or residue naming needs to be fixed.

Do you have any idea why it is happening?
Thank you in advanced.
Regards,
Ali





-----Original Message-----
From: gromacs.org_gmx-users-bounces at maillist.sys.kth.se
<gromacs.org_gmx-users-bounces at maillist.sys.kth.se> On Behalf Of Justin
Lemkul
Sent: donderdag 8 november 2018 13:57
To: gmx-users at gromacs.org
Subject: Re: [gmx-users] pdb2gmx fatal error



On 11/7/18 1:05 PM, Ali Khodayari wrote:
> Dear gmx users,
>
>   
>
> I am trying to simulate a cellobiose, using GROMOS53a6CARBO. The atom 
> names were modified according to the rtp file of the force field. Yet, 
> I get the following error while I perform pdb2gmx command:
>
>   
>
> Fatal error:
>
> Residue 4 named GLC of a molecule in the input file was mapped to an 
> entry in the topology database, but the atom C6 used in that entry is 
> not found in the input file. Perhaps your atom and/or residue naming needs
to be fixed."
>
>   
>
> I also tried to delete the hydrogens in the pdb file but the error 
> changed to the following:
>
>   
>
> Fatal error:
>
> Residue 876814369 named GLC of a molecule in the input file was mapped 
> to an entry in the topology database, but the atom C3 used in an 
> interaction of type improper in that entry is not found in the input 
> file. Perhaps your atom and/or residue naming needs to be fixed.
>
>   
>
> Ignoring the hydrogens through -ignh will give the first error as well.
> Then I added the GLC residue to the residuetypes.dat and the error 
> changed
> to:

Your problem is not related to hydrogens. pdb2gmx is complaining about
carbon nomenclature.

http://www.gromacs.org/Documentation/Errors#Atom_X_in_residue_YYY_not_found_
in_rtp_entry

>   
>
> Fatal error:
>
> atom N not found in buiding block 1GLC while combining tdb and rtp
>
>   

This error comes from letting pdb2gmx apply default protein terminal
patches. For a carbohydrate, you probably should have definitions for
properly constructed reducing and non-reducing ends (e.g. different from
internal residues) and apply no terminal patching.

-Justin

--
==================================================

Justin A. Lemkul, Ph.D.
Assistant Professor
Virginia Tech Department of Biochemistry

303 Engel Hall
340 West Campus Dr.
Blacksburg, VA 24061

jalemkul at vt.edu | (540) 231-3129
http://www.thelemkullab.com

==================================================

--
Gromacs Users mailing list

* Please search the archive at
http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting!

* Can't post? Read http://www.gromacs.org/Support/Mailing_Lists

* For (un)subscribe requests visit
https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a
mail to gmx-users-request at gromacs.org.



More information about the gromacs.org_gmx-users mailing list