CHARMM Development Project Forums User Discussion & Questions Parameter Set Discussion Patch for N-sultated Glucosamine - part 2

Hi all,

After setting up the patch for adding the sulfamate to the N- glucosamine, I got the folloing error:

CHARMM> patch nhshb S 2 setup
ATOM S AGLCNA 2 S ADDED.
ATOM S AGLCNA 2 O2 ADDED.
ATOM S AGLCNA 2 O7 ADDED.
ATOM S AGLCNA 2 O8 ADDED.

Message from MAPIC: Atom numbers are changed.
*** LEVEL -3 WARNING *** BOMLEV IS -3
BOMLEV HAS BEEN SATISFIED.supposedly TERMINATING.

I cannot explain which atom numbers changed and why. The patch supposedly adds SO3 to the AGLCNA already deacetylated by another patch.

Thank in advance

Tarsis

WRNLEV 1 BOMLEV -3 = . Sorry, you're on your own. Please review the READ THIS FIRST topic.

Edit: in case you wondered why we're so fanatic about our users not touching WRNLEV or BOMLEV, your fatal error is not caused by the change in atom numbers. CHARMM would likely tell you the real cause of the problem if you wouldn't suppress it by changing WRNLEV .

I'm sorry,

I ran it before with BOMLEV 0 but wanted to test whether it would work with -3.

That's how the script ends with BOMLEV 0

CHARMM> patch amin S 2 setup
ATOM S 2 AGLCNA C AND ALL REFERENCES TO IT DELETED.
ATOM S 2 AGLCNA O AND ALL REFERENCES TO IT DELETED.
ATOM S 2 AGLCNA CT AND ALL REFERENCES TO IT DELETED.
ATOM S 2 AGLCNA HT1 AND ALL REFERENCES TO IT DELETED.
ATOM S 2 AGLCNA HT2 AND ALL REFERENCES TO IT DELETED.
ATOM S 2 AGLCNA HT3 AND ALL REFERENCES TO IT DELETED.
ATOM S AGLCNA 2 S ADDED.
ATOM S AGLCNA 2 O2 ADDED.
ATOM S AGLCNA 2 O7 ADDED.
ATOM S AGLCNA 2 O8 ADDED.

Message from MAPIC: Atom numbers are changed.
DELTIC: 6 bonds deleted
DELTIC: 11 angles deleted
DELTIC: 13 dihedrals deleted
DELTIC: 2 improper dihedrals deleted
*** LEVEL -3 WARNING *** BOMLEV IS 0
BOMLEV HAS BEEN SATISFIED. TERMINATING.

ABNORMAL TERMINATION
MOST SEVERE WARNING WAS AT LEVEL -3

As mentioned in my last post, you need to remove the WRNLEV command as well. There's still information missing from your output.

Yep, as you said it before, haste makes waste

I removed WRNLEV and got what the error was. I will try to fix it by myself and then post the results/questions when they appear.

Thanks again for the patience Kenno.

I think I got it (except by some nasty clashes between the sulfur S1 and O7 and HN nitrogen).

Does anyone know how to fix that?

Thanks all again,

Tarsis

Now you're talking! The clash can be relieved by editing the values (especially the dihedral) in the IC C1 C2 N HN entry. I speculate it arose after editing IC C1 C2 N S1 without doing the above. To make the hydrogen "follow" automatically when editing the dihedral associated with the heavy atoms, it is recommended to use an improper IC entry, like this:Where the 120 can be changed to -120 depending on the pyramid flip, and the zeroes can be substituted manually with the correct coordinates, or automatically with IC PARAM.

On an unrelated note:

• You can suppress the charge warning at the beginning of your output by changing the total charge in your topology file like this: PRES AMIN -1.00 .
• It is good practice to leave the main force field files untouched, and make a private self-contained stream file for any additions.

See the CGenFF files and tutorials for examples illustrating all of the above.

Hi Kenno,

I managed to fix the clash by editing the IC entry as you said, tks by the way for all your help. But now two questions arose.

1) There seems to be a problem with the coordinates for the BGLC atoms (this error does not reflect in anything, just annoys me).

CHARMM> read coor univ unit 1 offset 0
SPATIAL COORDINATES BEING READ FROM UNIT 1
TITLE> NONE
TITLE> *
** WARNING ** NO COORDINATES FOR 1 1 BGLCA C1
** WARNING ** NO COORDINATES FOR 2 1 BGLCA H1
** WARNING ** NO COORDINATES FOR 3 1 BGLCA O1
** WARNING ** NO COORDINATES FOR 4 1 BGLCA HO1
** WARNING ** NO COORDINATES FOR 5 1 BGLCA C5

2) Where can I find impropers that may match those entries?

: No improper parameters for 2 ( SC OC2DP NG2S3 OC2DP )
: No improper parameters for 3 ( NG2S3 SC CC3161 HCP1 )
: No improper parameters for 4 ( SC OC2DP NG2S3 OC2DP )
: A TOTAL OF 3 MISSING PARAMETERS


I will, when done with this parametrization, generate the stream file. Thanks for reminding me that!

All the best

The "NO COORDINATES" error occurs because you may not using READ COOR UNIV correctly, and because the PDB format does not support the 5- and 6-char residue names used by the all36_carb force field.

Concerning the impropers, you should never define them on nonplanar/tetrahedral centers (and not even on all planar centers; see this FAQ). So just remove the 3 superfluous IMPR lines from your topology file and you're done (I'm assuming the sulfamate nitrogen is not planar).