Hi Ed,
If the purpose of the combination is to use Morph Conformations, then I think you're in for a world of hurt unless you use the 'combine' method.  One problem with the 'cat' method is the serial numbers as you surmised.  If you have any non-standard residues that require CONECT records then the serial numbers will be a real issue.  Another problem is that if you have any chains in models 8 and 9 that duplicate the ones you're using from #6 (a-p) or duplicate each other then Morph Conformations will probably fall over.  'combine' will rename chains that are in conflict and renumber problem residues.  'write' with the combined model will produce unique serial numbers.
So your previous commands:

select #6:.a-p #8 #9
write selected relative 0 #6,8,9 /path/to/file.pdb
 ~select

could instead be:

sel #6:.a-p
sel invert sel
del sel
combine #6,8,9 refMol 0 modelId 7
write #7 /path/to/file.pdb

BTW, you have to use a daily build to get the 'modelId' part of the 'combine' command.
If your models #8 and 9 are just small molecules then you may be able to get away with the 'cat' method by stripping CONECT records in addition to END records -- making Chimera come up with the connectivity itself (though if the residues had the same number and chain ID as other residues...).

--Eric

On Apr 1, 2009, at 1:32 PM, Edward Brignole wrote:

Great suggestion, I'll just use cat and strip the END lines. Since I want to then use these with morph conformations will I also have to resequence the atom id's?

Ed

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Edward Brignole
NIH Kirschstein Postdoctoral Fellow
Francisco Asturias Lab, CB227
Center for Integrative Molecular Biosciences
The Scripps Research Institute
www.scripps.edu/~brignole

brignole@scripps.edu
443-653-2070 (cell)
858-784-8598 (lab)



-----Original Message-----
From: Eric Pettersen [mailto:pett@cgl.ucsf.edu]
Sent: Wed 4/1/2009 1:26 PM
To: Edward Brignole
Cc: chimera-users@cgl.ucsf.edu BB
Subject: Re: [Chimera-users] write selected command

Other possibilities include using the "combine" command to combine 
models 6, 8, and 9 into a single model (with model 0 as the 'refMol') 
and then use the write command on that (omitting 'relative 0'), or 
writing the models to separate files and using 'system cat file1 file2 
file3 > file4' to combine them (though there would be END records 
between the models that way).

--Eric

                         Eric Pettersen
                         UCSF Computer Graphics Lab
                         http://www.cgl.ucsf.edu


On Apr 1, 2009, at 1:11 PM, Elaine Meng wrote:

> Hi Ed,
> The "write" command only allows you to save one model at a time.
> <http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/write.html>
>
> To save multiple models to one PDB file you have to use the GUI
> ("File... Save PDB" or "Actions... Write PDB").
> <http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/savemodel.html#pdb>
>
> Sorry about that,
> Elaine
> -----
> Elaine C. Meng, Ph.D.                          meng@cgl.ucsf.edu
> UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab
> Department of Pharmaceutical Chemistry
> University of California, San Francisco
>                       http://www.cgl.ucsf.edu/home/meng/index.html
>
> On Apr 1, 2009, at 1:02 PM, Edward Brignole wrote:
>
>> Elaine and co,
>>
>> I have a mess of models that I'm opening, repositioning a ligand
>> using match to various positions in each model. No problem there.
>> For each model and ligand position I select the correct chains from
>> that model with the repositioned ligand models but can't manage to
>> save coordinates. Obviously there's the save pdb dialog but for all
>> these models and ligands this will be more convenient scripted into
>> chimera commands. I've got it all working except this:
>>
>> select #6:.a-p #8 #9
>> write selected relative 0 #6,8,9 /path/to/file.pdb
>> ~select
>>
>> The part it doesn't like is the model_numbers and I've tried
>> various permutations without success. The only way I can get it to
>> work is if I only specify one model number.
>>
>> Can you please help me figure out how to phrase this command
>> correctly? An example or two on that commands page might make the
>> syntax easier to decipher.
>>
>> Thank you for your excellent program and support.
>>
>> Ed
>>
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> Edward Brignole
>> NIH Kirschstein Postdoctoral Fellow
>> Francisco Asturias Lab, CB227
>> Center for Integrative Molecular Biosciences
>> The Scripps Research Institute
>> www.scripps.edu/~brignole
>>
>> brignole@scripps.edu
>> 443-653-2070 (cell)
>> 858-784-8598 (lab)
>>
>>
>>
>>
>> _______________________________________________
>> Chimera-users mailing list
>> Chimera-users@cgl.ucsf.edu
>> http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users
>
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