[Chimera-users] Command Patch problem

[Elaine Meng]

Hi Mahad,
I can't tell what exactly is the problem, but make sure that you have only two atoms selected (not the whole residues), the C at the end of one peptide and the N at the start of the other.   Then you should be able to choose the "C-N peptide bond" option, and then apply.  You do not need to position the structures before joining them.

Something like the example "select" command I gave in the earlier message should select only two atoms.  Or, if you prefer to use the mouse to select from the screen, you would first need to show the atoms... for example:

preset apply int 2

... use Ctrl-click to select the carbonyl C at the end of the first peptide, then Shift-Ctrl-click to select the amino N at the start of the second peptide.   Then choose "C-N peptide bond" in the Join Models part of Build Structure, then click Apply.

I hope this helps,
Elaine
----------
Elaine C. Meng, Ph.D. 
UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab
Department of Pharmaceutical Chemistry
University of California, San Francisco

On Jan 26, 2013, at 4:06 AM, mahad iou muddei addò wrote:

> Dear Elaine, thank you so much because i understand my mistakes, but i'm afraid i have to ask you something again. I've done as you said, so i selected the residues and then used join models function but the apply button cannot be clicked. I don't understand if this happens because:
> 
> -of the selected residues
> -the 2 proteins have to be already in position for the bond
> -something to be done before using join models
> 
> I'm sorry to trouble you so much
> Sincererly
> 
> Mahad
> 
> 2013/1/25 Elaine Meng <meng at cgl.ucsf.edu>
> Hi Mahad,
> If I read your mail correctly, there is no overlap between the two sequences.  You would only use "match" to overlap structures, i.e. to try to put one group of atoms on top of another group of atoms (with exactly the same number of atoms).  As the error message said,
> 
> > match #0:422 #1:442
> > Unequal numbers of atoms chosen for evaluation
> 
> ... residue 422 in #0 and residue 442 in #1 do not have the same numbers of atoms, which is not surprising if one is an "R" and the other is "D." You could specify using backbone atoms only to get the same numbers, for example:
> 
> match #0:422 at n,ca,c,o #1:442 at n,ca,c,o
> 
> HOWEVER: from your description it sounds like you do not really want to match (put 422 on top of 442), but instead you want to join the two peptides (add peptide bond between 422 and 442).  In that case you should use the Build Structure tool (in menu under Tools... Structure Editing), Join Models section.
> 
> <http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.html>
> <http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.html#join>
> 
> First select the two atoms you want to bond, maybe something like this:
> 
> select #0:422 at c #1:442 at n
> 
> ... and then use the C-N peptide bond option in Join Models.
> I hope this helps,
> Elaine
> -----
> Elaine C. Meng, Ph.D.
> UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab
> Department of Pharmaceutical Chemistry
> University of California, San Francisco
> 
> On Jan 25, 2013, at 6:57 AM, mahad iou muddei addò wrote:
> 
> > Hi, i'm working with chimera for the first time. I need to patch 2 structures that i have the PDBs. I've already read the user guide and try to follow the instructions for making a controlled superimposition of the two structures.
> > These are my two sequence:
> >
> > 1)RKYVYSLYWSTLTLTTIGETPPPVRDSEYFFVVADFLIGVLIFATIVGNIGSMISNMNAARAEFQARIDAIKQYMHFR
> >
> > 2)DSSRRQYQEKYKQVEQYMSFHKLPADFRQKIHDYYEHRYQG-KMFDEDSILGELNGPLREKIVNFNCRKLVASMPLFANADPNFVTAMLTKLKFEVFQP
> > GDYIIREGTIGKKMYFIQHGVVSVLTK-NKEM--KLSDGSYFGEICLLT------RGRRTASVRADTYCRLYSLSVDN
> > FNEVLEEYPMMRRAFETVAIDRLDR/
> >
> > I need to create a structure like this:
> >
> > RKYVYSLYWSTLTLTTIGETPPPVRDSEYFFVVADFLIGVLIFATIVGNIGSMISNMNAARAEFQARIDAIKQYMHFRDSSRRQYQEKYKQVEQYMSFH
> > KLPADFRQKIHDYYEHRYQG-KMFDEDSILGELNGPLREKIVNFNCRKLVASMPLFANADPNFVTAMLTKLKFEVFQP
> > GDYIIREGTIGKKMYFIQHGVVSVLTK-NKEM--KLSDGSYFGEICLLT------RGRRTASVRADTYCRLYSLSVDN
> > FNEVLEEYPMMRRAFETVAIDRLDR/
> >
> > I know the position of the aa involved but after i launch the command trough command line it gives me errors like
> >
> > match #0:422 #1:442
> > Unequal numbers of atoms chosen for evalutation
> >
> > What am i doing wrong?
> > Thanks, sincererly
> >
> > Mahad
>